Learning Meaning Through Conceptual Reconstruction-

 

A Learning/Teaching Strategy for Secondary Students

 

 

 

 

 

 

 

Dennis W. Sunal

The University of Alabama, Box 870231,Tuscaloosa, Alabama

dsunal@bamaed.ua.edu

Learning Meaning Through Conceptual Reconstruction-

A Learning/Teaching Strategy for Secondary Students

Dennis W. Sunal

The University of Alabama, Box 870231,Tuscaloosa, Alabama

dsunal@bamaed.ua.edu

Abstract

Students bring to any science lesson experiences, ideas, and skills related to the content. Because of the prior knowledge students bring to a lesson, teaching so that the lessonís content has meaning to students involves helping them reconstruct their existing ideas. This strategy is called conceptual reconstruction. It is vastly different from teaching new ideas to be added to a blank mind. Research on conceptual reconstruction and the methods in classroom practice that facilitate it are discussed. Specific examples of science instruction using the learning cycle strategy are provided to demonstrate facilitation of student learning through conceptual reconstruction.

Introduction

Knowledge is found in the minds and bodies of thinking beings (Johnson, 1987). Learning is the construction of knowledge by individuals as sensory data are given meaning in terms of their prior knowledge. It is an interpretive process, involving constructions of individuals and social collaboration (Tobin, Briscoe, & Holman, 1990, 411).

Learning and teaching are closely connected in a way similar to the relationship between advertising and buying an expensive product, perhaps a new automobile. One can have buying (meaningful learning) with and without advertising (teaching). Much of the time and effort devoted to advertising (teaching) occurs without buying (meaningful learning). Just as the advertising executive strives to increase the effectiveness of the advertising to produce more buying, the teacher strives to increase the effectiveness of their teaching to produce more meaningful learning. Meaning can only be formed by students in their own minds (Saunders, 1992 ). Students cannot be passive during learning. Teachers can facilitate meaningful learning by planning and using experiences that engage students in working with ideas in their own minds and with their own actions (Yager, 1991). Meaningful learning must be an active construction process. It is a process that involves and depends on: the background knowledge the learner brings to a situation, whether the learnerís attention is focused on the ideas being presented, and the mental and physical actions of the learner as she works with objects and events in testing prior or new tentative versions of a new idea.

Students Learning with Examples from Todayís Science

One unaddressed aspect of scientific literacy in higher education is moving students from novice "seeing as" observers or naive "seeing that" observers to informed "seeing that" observers. What "seeing" meant to scientists in the 1800s, termed "seeing as" observations, is different from what seeing means to scientists in the 1990s, "seeing that" observations. A fundamental change has occurred in scientific observation and, thus, there are changes in what counts as observational evidence in the formulation of science generalizations and scientific theories (Duschl, 1990).

The role of human senses in data collection have become deemphasized in favor of instruments and methods based on fundamental theories in science. This deemphasis leads to the result that it is increasingly more difficult to explain what and how we know.

"Seeing as" observations are carried out with little prior knowledge, a literal description of patterns in nature that is possible to even the uninitiated in science. This involves seeing the irregular pattern in the placement of stars in the sky, the similarities and differences between structures used to build airplane wings, and the angle of reflection of light off surfaces. Data is represented by things which can be sensed or developed directly from observations. This data develops generalizations such as the refraction of light, velocity, and conduction of heat.

"Seeing that" observations can only be interpreted with extensive prior knowledge. Not everyone can see this way. It takes a large amount of experience. For example this type of observing occurs when seeing the disease prone nature of crops in satellite data, observing the movement of crustal plates of the earth, seeing the magnetosphere of the earth, or detecting the presence of a black hole in a galaxy. Data evolves from theoretical considerations which are abstract and not sensed directly. This data develops theory such as bosons and hadrons make up all matter as viewed with particle accelerators, plate tectonics as derived from magnetic anomalies and complex earthquake patterns, biological evolution as derived from statistical probabilities in the diversity of life on Earth.

In the classroom much of what we do should involve moving students from novice "seeing as" observers or naive "seeing that" observers to informed "seeing that" observers.

This is what todayís new pedagogy using conceptual reconstruction is attempting to do. Learners, students or scientists, revise and replace their knowledge as they acquire experience and understanding. A studentís prior knowledge must be linked to every phase of the conceptual restructuring process. We must teach students to think critically about new ideas presented and to creatively apply and evaluate the knowledge of science. To know something in science is to reconstruct and construct meaningful relationships among concepts.

Final form statements which fill traditional textbooks and classrooms do not convey meaning. Final form science teaches the conclusions of science as fact. Final form science is traditionally taught and learned through memorization. We teach knowledge without the procedures for understanding the meaning of the content. The important goal of effective modern science, mathematics and engineering teaching is not only to teach the new ideas meaningfully which develop at a quickening pace, but also the changes to our meanings of the investigative process and the characterizations of knowledge - what we mean by observation, the nature of evidence, the methods of science, mathematics and engineering, and what we know (our theoretical viewpoint). We must help students learn how to learn, how knowledge comes to be, if we are to teach the meaningful knowledge of the 21st century.

Knowledge Representation

Knowledge begins when the learner actively works with experiences, objects and events. Knowledge is actively built up in the learnerís mind as a new construction of sensory information from the world, and a reconstruction of previous knowledge. Sources of knowledge can be described as being of two kinds (Vygotsky, 1962). Knowledge can be constructed from everyday interaction with the environment or through formal instruction. Everyday knowledge is intuitive and influenced by language and culture, often referred to as naive knowledge forming the personís reality. Formal instruction is someone elseís knowledge and interpretation of the world, someone elseís reality. It is referred to as classroom knowledge or scientific knowledge in this paper. The mixing of naive knowledge and classroom knowledge is referred to as prior knowledge. For active learning to occur, classroom experiences must be first perceived by the student. Then the student must take this perception and mentally reconstruct it in relation to already existing prior knowledge. This reconstruction of what was perceived in the mind of the student is her representation of the classroom experience. This representation was transformed to fit the studentís current background knowledge. Once the student has fit it in with what is already known in their mind, the perception of the classroom experience is completed. The student has now constructed meaning. Because the experience has been given meaning, the student will be able to apply this new knowledge in situations different from where it was learned.

Learning through studentsí active mental and physical involvement is appropriate for more complex forms of learning beyond rote memory and recall learning. It is called meaningful learning. These forms of learning involve:

1. understanding concepts based on experiencing, identifying, selecting, and/or classifying facts (e.g. understanding that heat can be transported, conducted, or stored in an object, specific heat)

2. understanding generalizations by linking concepts (e.g. predicting how fast heat travels in a type of material is based on physical properties of the material),

3. understanding schemata and theory (e.g. how things move - schemata are situation specific and are not transferred across situations as in motion in free fall and motion down an inclined plane and theories are generalized systems of relationships as in the theory of motion or theory of matter).

4. developing critical thinking skills as in basic scientific process skills (e.g. classifying rock crystals based on previous knowledge of geometric shapes), and

5. developing attitudes and dispositions about the physical world (e.g. willing to suspend judgment about an event or problem situation until a sufficient amount of evidence is available to form a reasonable conclusion). (See Figure 1)

_____________________

Figure 1 about here

_____________________

Understanding that knowledge develops from the individualís attempts to construct representations in her mind is important in teaching. The organized, structured, and abstract bodies of information that a person already has in her mind are used in learning new content and determine how the information is perceived, represented, transformed, transferred, and used. This is what the learner understands about the event. These knowledge representations are the concepts, generalizations, theory, and thought processes that are used in making sense of real world objects and events. They represent all levels of understanding from the meaning of

"Venus is an evening star"

to the idea that

"matter is composed of tiny, moving particles."

Science Knowledge Structures

A knowledge "representation" in the mind involves a concept, generalization, theory, thinking skill, or disposition. Each representation is related, linked, to other representations in the mind. The parts of a specific representation are also related to each other. The concept, generalization, theory, thinking skill, or disposition and the relationships within it and with other representations together form a knowledge structure. This is a complex set of relationships. Building relationships gives meaning to representations. An isolated fact that is not linked to other pieces of knowledge, doesnít give the learner much to work with. For example, the knowledge structure for "pond" might include broad generalizations about ecosystems, medium level generalizations about food webs and food chains, more narrow generalizations, concepts and thinking skills involving breeding mosquitoes and types of fish, and specific remembrances of smells and feelings about events and things experienced in ponds (see Figure 2). The important aspect of a pond knowledge structure is that once any element in the structure is activated the entire structure can be searched, recalled, and brought to bear on understanding a new experience. The mention of mosquitoes in a lecture or chapter dealing with food webs may lead a student to think about fish eating the mosquito and other types of insects all common to the habitat of the pond. Links with other knowledge structures, forest or desert ecosystems, may lead to the types of insects not related to the pond or wetland habitat.

Experts, scientists, knowledge structures contain many more linkages than novice learners. However, the more extensive information which experts possess is not necessary for the difficulty of problems faced in school or in everyday life. The difference, needed for success, is in the extent of linkages within and between knowledge structures (Chi, M., Feltovich, P. & Glaser, R., 1981). These differences in linkages reflect differences in accuracy, abstractness, and structure. Didactic instruction in classrooms is effective in providing discrete bits of information in students minds. Typical low student ability at problem solving of all types suggests that the organization of linkages of the information resulting from didactic instruction is not sufficient. Cognitive learning theory implies strategies that can result in highly linked information into more adequate knowledge structures useful for problem solving in school classrooms and in the real world.

_____________________

Figure 2 about here

_____________________

Conceptual Learning in Science

Topics that are a typical part of the school curriculum and textbooks include areas such as matter, ratios, magnetic fields, plants, functions, photosynthesis, water habitats, and forests. After elementary school these fields are studied at least twice, three years apart, in a step fashion. Each time the concepts are studied, they are studied in greater detail and expanded to much deeper and more abstract contexts. The studentís prior knowledge is used in this progression. The teacherís task is to change students prior knowledge structures so they fit with more accurate, abstract, and structured explanations of the events and processes they are involved with. This process of learning involves making different kinds of changes in studentís knowledge structures. Some changes involve reconstructing existing structures. Others involve constructing new structures.

Three types of learning can take place;

* some learning consists of acquiring totally new knowledge (e.g. double bonding in organic chemistry),

while most learning

* is incorporated within prior knowledge (Piaget called this assimilation), or

* modifies prior knowledge (Piaget called this accommodation) (Campbell, 1974; Petrie, 1981).

Acquiring New Knowledge Structures

Acquiring new knowledge directly from experience makes little sense without assuming the person has some prior knowledge within which the new experience is interpreted and related. The new experience would be confusing or might not even be perceived if connections arenít made to prior knowledge the person already has. Sometimes we have to look at a scene or event many times before perceiving an important detail. The particles which make up protons, called quarks, are an example of new knowledge which has little meaning to students who are novices to science.

Acquiring Knowledge by Assimilation

Knowledge presented in classrooms may not be in conflict with what is already known. Introducing a different species of tree, silver maple, or expanding the idea that solids expand or contract due to temperature through experiencing the expansion of cracks in concrete on a cold day represent assimilation. There is no reason to modify prior knowledge, the information reinforces existing ideas. The new knowledge becomes integrated into the existing prior knowledge and becomes part of the personís reality.

Acquiring Knowledge by Modifying Prior Knowledge - Restructuring

Restructuring represents changes in linkages occurring within a specific knowledge structure and between knowledge structures in studentís minds (Rumelhart & Norman, 1981). Conceptual restructuring involves accommodation and occurs through making modifications of prior knowledge through redefining previously-known knowledge (conceptual resolution) or replacement of existing structures with new irreconcilable ones (conceptual change). It is only through this process that real growth takes place in studentís thinking. This is the important learning, meaningful learning, which must take place in classrooms to create the goals required for scientific and mathematical literacy.

Restructuring can vary in its extent. It can involve a minor change as in conceptual resolution. Or it can involve a major change, a conceptual change, taking place gradually over years in oneís view of the world and in the thought processes brought to bear on the world. Conceptual change can be said to occur when a new knowledge structure differs from the old one in terms of the individual concepts involved, the relationships between the concepts, and the extent and type of the phenomena the knowledge structure can explain. Restructuring occurs along a continuum from minor to major restructuring.

Conceptual change has been described as occurring in one limited area with no carryover to other areas (Carey,1986; Gelman & Baillargeon, 1983; Mandler, 1983). This means that it may occur in one area of science but it is not carried over to another area. For example one can learn the concept of interaction at a distance and reversibility in magnetic interactions. Learning this idea in magnetic interactions does not create understanding of interaction at a distance and reversibility in heat concepts or in light concepts. Conceptual change must be facilitated over and over in each area of science knowledge. While transfer of learning does occur between knowledge structures, it is a rare and difficult process requiring much experience and substantial knowledge in an area (Champagne, Gunstone, & Klopfer, 1985).

According to this view, students begin with a few knowledge structures about the world and through conceptual resolution enlarge them and create new ones. They might learn about interaction at a distance and reversibility in magnetism and create a knowledge structure for it. Then they might learn about interaction at a distance in heat and link it to the earlier knowledge structure they had on heat. Much later in the process, as an example of conceptual change, they form a new knowledge structure of interaction at a distance and reversibility, and link it to magnetism and heat. Later they apply it in general as field theory. This process occurs over time, perhaps years. This increased knowledge is brought about by experience and classroom instruction aimed at conceptual resolution and change processes. To help students learn, teachers must understand that their short term goals involve developing studentsí knowledge representations and linkages between them. Teachers, also, need to understand that they are working towards the longer term goal of changing knowledge structures.

If students are to develop a completely new knowledge framework compared to the one they had as elementary students, major restructuring will be needed, not just assimilation of information. Classroom pedagogy should work towards conceptual change. The science curriculum should not focus on expanding experiences of simple facts about magnets or heat or with the final form conclusions or rules about magnets or heat. Instead, classroom work must move towards exploring the more numerous and complex relationships between these concepts and their linkages with the final abstract conclusions. Classroom experiences should help students move from working with real objects, to representations of real objects (analogies and models), and finally to their representation in more abstract and symbolic forms. Students have to learn to use higher forms of thinking skills to develop more abstract concepts and link them. Finally, teachers must understand that all this development leads to the ultimate goal of education, intellectual development.

Awareness of the need for restructuring science knowledge has implications for learning and teaching. First, it is better to start with and expand upon old knowledge structures and to relate new information to what is already known. Second, existing knowledge should be used differently to support new knowledge depending on whether assimilation or accommodation types of restructuring is the goal. Old knowledge structures interfere with the development of very new ways of viewing the world. Students will sometimes find it difficult to drop an old way of viewing things and adopt a new one based on a few minutes of contradictory classroom experience. Thus, supportive classroom strategies aimed at conceptual resolution restructuring will be different and are more intensive than for assimilation of knowledge restructuring.

Reconstruction of Prior Knowledge - Conceptual Resolution and

Conceptual Change:

Elements of an Effective Pedagogical Strategy

To create learning in students, teachers must go far beyond traditional teaching strategies. Presenting information about an idea through lecture or reading, followed by review of the information, focuses primarily on mental recall actions and produces knowledge which is not meaningful. Students must be involved in activities which foster restructuring of prior knowledge. Restructuring requires

1) motivating students to recall related prior knowledge,

2) connecting the new idea to studentís prior knowledge,

3) building an awareness of inconsistencies of thought,

4) allowing students to compare (confront) prior knowledge with the new knowledge,

5) using analogies, metaphors, and physical models and the awareness of inconsistencies they may produce,

6) providing opportunities for students to test the new idea and to use (transfer) the new idea successfully,

7) helping students reconstruct ways of perceiving, and

8) helping students reconstruct prior knowledge.

Specific pedagogical implications are related to this view of learning as an active process.

Five basic implications for teaching are:

1. use prior knowledge in creating new, meaningful learning,

2. motivate students to learn,

3. link new information to prior knowledge,

4. integrate knowledge, and

5. encourage growth of cognitive and metacognitive processes.

Knowledge structures include perceiving, processing and critical and creative thinking skills and dispositions as well as concepts, generalizations, and theory. Strategies that help form new thinking processes are: reflection, restructuring of ideas, and learning from others. The term, conceptual restructuring, is used here to refer specifically to the formation of thinking processes and using those thinking processes in the construction of new knowledge. Conceptual restructuring is part of a complex process where three phases occur. First, specific sensory data is taken into the short term memory from the sensory memory where selection of important information sends a small portion on to the short term memory. Second, through conceptual restructuring processes taking place in the short term memory, the process of knowledge construction takes place. Third, using the new idea in a variety of tasks stabilizes it as a thought routine and facilitates its final organization and storage in the long term memory. Conceptual restructuring goes on all the time in all parts of our lives. It may involve processes that deal with physical tasks or with word problems. Each new idea represents a relatively consistent approach to similar problems. Feedback from the personís thoughts and actions related to problems encountered strengthens the thinking processes a person finds to be effective in dealing with problems. Repeated conceptual restructuring using many thinking processes eventually leads a person to function at a higher developmental level.

Conceptual Resolution

Before students experience any formal teaching, they are likely to have formulated their own ideas, personal knowledge, which may enable them to explain and predict phenomena to their own satisfaction, but which are in conflict with classroom knowledge. Other terms used for this personal knowledge are student misconceptions, naive science, personal knowledge, alternative conceptions, or conceptual barriers. General characteristics of these naive ideas are they start early and continue lifelong, they are personal and may differ from other students, they are subtle and unrecognized by teachers, remain separated from classroom knowledge, difficult to change even when clear evidence is presented, and are contradictory to classroom knowledge (see Figure 3 for examples). Misconceptions start from many sources;

1) family and home situations through misleading language and incorrect or mythical explanations,

2) mass media through misleading language and false wording in advertisements,

3) classroom teaching through misleading terminology and inaccurate explanations and analogies, and

4) other sociocultural sources.

Concepts regarding heredity and AIDS are two examples. See Figure 4 for examples of student misconceptions on heat. Due to unfamiliarity with the scientific language used, students in classrooms may adopt different strategies to alleviate confrontation;

1) ignore the teacher because the words contain no comprehension,

2) pronounce, spell, or memorize meaningless words,

3) mismatch words and assign inaccurate meanings,

4) assign several incompatible meanings to the terms depending on the context used, or

5) attach scientific meaning to common words.

When students are presented with ideas in classroom lessons, for example, they have to modify and reconstruct their own ideas in order to accommodate new ideas. Four conditions need to exist to help students to discard an old belief and accept a new ideas based on real world fact:

1. a student must be dissatisfied with his or her existing idea (confrontation),

2. any new idea must be comprehensible to the student (conceptual clarity),

3. a new idea must appear as plausible as the studentís own misconception (plausible), and

4. a new concept or explanation has to be more useful than the previously held belief for solving problems or making predictions (validity).

Learning new ideas requires a willingness and an effort on the part of the learner. Teaching involves helping each student to construct for herself, scientifically and mathematically accepted ideas. Learning should be viewed as how much studentsí ideas change over time. Teachers attempting to reconcile misconceptions must work on changing prior knowledge rather than only on introducing new knowledge. The starting point of a teaching sequence is the ideas students bring with them. The role of the teacher is that of diagnostician and prescriber of appropriate learning activities.

A personís interactions with the environment may lead to contradictions, expectations that are not confirmed by what actually happens. When this occurs, the stable state of mind is upset and a change in thinking processes can be brought about through conceptual restructuring, mental processing in the short term memory. Conceptual restructuring forms new thinking processes that integrate new ideas/or skills and resolve apparent contradictions in the framework of old thinking processes. Conceptual restructuring involves a person in

1) analyzing a problem situation,

2) considering tentative solutions based on oneís previous experience,

3) trying out the tentative solutions,

4) evaluating the effectiveness of the tentative solutions, and

5) using new approaches when trials of the first tentative solutions are not successful.

Awareness of oneís own reasoning is important for conceptual restructuring leading to higher level thinking processes. Specific aspects of pedagogy to concentrate on during this overall conceptual restructuring process include broaden the range of application of a conception, differentiate a conception, build experiential bridges to a new conception, relate and update prior knowledge to new conceptual problems, import a different model or analogy, progressively shape a conception, or construct an alternative conception (see Figure 5).

_____________________

Figures 3, 4, & 5 about here

_____________________

Whatever a personís specific method of coping with a new challenge, when the changes required are not too great, conceptual resolution, the individual is more likely to reorganize existing thinking processes into more appropriate new ones. For example,

"A person may notice and be puzzled by the fact that there are different sized spaces between tree rings observed in a log. Looking at the rings one finds 3 or 4 spaced close together and the next set of 5 rings spaced further apart. Recall of prior knowledge has lead the person to believe that the rings reflect yearly growth and that rings are always spaced the same distance apart. A confrontation occurs to the personís old way of thinking. The old thought pattern will remain unless planned conceptual resolution pedagogy is experienced. The person then needs to compare this log cross-section to other logs from different trees in different locations. The patterns which show up have similarities and differences. The experience leads to inferences about important variables relating ring spacing to health of the tree, amount of rainfall, severity of the spring and summer growing season, or type of soil. Testing is then possible, after hypotheses are formulated, leading to a possible conclusion that ring spacing is related to a treeís environment."

Restructuring occurs when patterns can be found that explain the puzzle. Confirmation of a new pattern through its application to other experiences will maintain the new stable mental state until new contradictions occur. When these new contradictions are encountered the stable mental state is upset as one finds the situation puzzling. Eventually a pattern is formed to explain the contradictions and a more complete idea results. A student will not accept and reconstruct a misconception unless in the eyes of the student the new idea is clear to the student, made plausible through experience in investigation and problem solving, and resolves the problem or confrontation better than the studentís original beliefs (Osborne and Freyberg, 1985). This is no different than a scientist or mathematician when presented with a new idea. The misconception will not be replaced until there something to replace it that is reasonable to the student. The process occurs over and over. The individual may find that comparing and contrasting items and characteristics in an environment is a process which doesnít always help explain a contradiction. Then she must use other higher order thinking processes. See Figure 6 for heat example summary of teaching and learning process.

_____________________

Figure 6 about here

_____________________

 

Conceptual Change

When the required changes in thinking processes are great, a conceptual change, a person may be required to abandon oneís commitment to a set of conceptual understandings by accepting another irreconcilable set. A person may be helped by peers, teacher, or graduate teaching assistants who can help in adopting the new explanation. For example,

"A person may notice and be puzzled by the fact that there are different types of trees in various forested areas. Recall of prior knowledge has lead the person to believe that trees are always the same everywhere. Trees are trees. A confrontation occurs to the persons old way of thinking The old thought pattern will remain unless planned conceptual resolution pedagogy is experienced. The person will need to compare and contrast trees in the various areas and explore the characteristics of the environment in each area. The individual then is lead to realize that the areas may differ by age, how long they have been left uncut, climate, or soil differences. Testing is then possible, after hypotheses are formulated, leading to a possible conclusion about tree succession."

Direct teaching, however, is usually not effective unless the learner has had extensive previous experiences with the thinking processes needed and can subsequently test them against her own observations (Harlen, 1985). She must get encouraging feedback from the environment in order for the interplay of thought and action, an essential part of conceptual restructuring, to continue until the new thinking processes are firmly established.

The teacher, traditionally, first lectures the solution to a problem carefully, then shows the student pictures of examples. This approach limits learning to the particular solution explained and focuses the learner on memorization of the idea. Since the student does not have to search her long term memory repertoire and possibly replace inadequate thinking processes, the old processes remain and are likely to be applied uncritically to the next problem they seem to fit. The new directly-taught solution is usually forgotten in a few days. Or, the learner is unable to recall it from memory unless the exact classroom conditions are reproduced. Learning by memory is encouraged by more direct teaching.

Instruction must be appropriate to studentsí own mental organization for it to be effective in helping them construct meaningful learning. Maturation and experience result in differing developmental levels of thought processes. An individualís developmental level reflects her ability to form concepts and generalizations through the use of a variety of thinking skills. These abilities develop with experience over time. See Figure 7 and 8 for a summary of the teaching and learning process involving prior knowledge.

_____________________

Figure 7 & 8 about here

_____________________

The Learning Cycle

Steps in an Effective Pedagogical Strategy for Conceptual Reconstruction

Several pedagogical frameworks have been devised that center on conceptual reconstruction. These frameworks are similar in that they center on a strategy which involves experience, interpretation, and elaboration. They all fit under the general name of the learning cycle (Karplus, 1979). See Appendix 1 for a review of several learning cycle models. The learning cycle is designed to adapt instruction to help students:

1) become aware of their prior knowledge,

2) foster cooperative learning and a safe positive learning environment

3) compare new alternatives to their prior knowledge,

4) connect it to what they already know,

5) construct their own "new" knowledge, and

6) apply the new knowledge in ways that are different from the situation in which it was learned.

The learning cycle has been effectively used with students at all levels to accomplish these purposes. This learning cycle approach helps students apply knowledge gained in the classroom to new areas or to new situations, because students:

1) are more aware of their own reasoning,

2) can recognize shortcomings of their conceptions as a result of being encouraged to try them out,

3) can apply procedures successful in other areas,

4) can search more effectively for new patterns, and

5) can apply what they learn more often in new settings.

Instruction must strengthen these tendencies in all students and discourage unquestioning acceptance of poorly-understood concepts, theories, and thinking skills.

The learning cycle involves students in a sequence of activities beginning with exploration of an idea or skill, leading to a more guided explanation (invention) of the idea or skill, and culminating in expansion of the idea or skill through additional practice and trials in new settings. See Figure 9. This sequence represents a single lesson on one concept lasting one to several instructional periods. Because of what occurs in each phase, the three parts of the learning cycle are called: exploration (experience), invention (interpretation), and expansion (elaboration). See Figure 10, 11, and 12. A teacher has a large number of choices in deciding how to provide instruction for students. The selection of pedagogical methods to use in teaching (e.g. lecture, inquiry, a hands-on approach, film, cooperative learning, etc.) should be determined by the

1) type of idea(s) or skill(s) to be taught,

2) developmental level and specific learning needs of the student,

3) part of the learning cycle the teacher is involved with,

4) form and content of studentís prior knowledge and the number and kind of instructional activities needed to create conceptual restructuring, and

5) type of knowledge representation required for the idea to be understood (Sunal, D. 1992 & Sunal and Sunal, 1990, 1991, 1994).

______________________

Figures 9,10,11 & 12 about here

_______________________

Exploration Phase

The Exploration provides students with the opportunity to bring out prior knowledge, explore a range of phenomena for themselves, and experience a confrontation to their own way of thinking (Driver, 1986). The goal is to produce some disequilibrium with experienced events so that prior knowledge is brought to the forefront and is available to the student for restructuring. The teacher is not concerned with right or wrong but rather with facilitating the gathering of data and observations of the students. The experience itself may produce restructuring in a few students on their own.

When a teacher begins to plan an exploration part of a lesson several decisions are made. An objective is selected or developed that is relevant to the curriculum and to the studentsí past experience in the area. Sometimes it is best to begin by thinking of a desired activity to be performed by students. With this activity in mind, it may be easier to develop a focus for the lesson objective. Most experienced teachers plan their lesson focus this way (Clark & Peterson, 1987). For example, an teacher may be planning a lesson for a textbook chapter which discusses the topic of soil. She may be thinking about an activity in which students are asked to dig a small hole in an undisturbed piece of forest ground. Imagining the activity or trying it out will lead the teacher to focus on the properties of the soil, layers of soil, and how the soil gets to be the way it is now seen. The activity will easily lead to the thinking skills needing development along with the science concepts. The skills would include observation and classification of various soil properties, communication and inferences relating to patterns found in the information, and predicting and hypothesizing leading to generalizations about soils. Thus, the lesson objectives would include

1. observing and classifying properties of soil a) color, b) particle size, c) stickiness, d) water holding capacity, and e) depth;

2. communicating and inferring patterns in the information discovered about soils; and

3. predicting, hypothesizing, and testing the patterns discovered at other "dig" sites and through indirect sources such as the textbook and library research materials.

Next, the teacher decides how the initial part of the lesson can best be used to prepare studentsí minds for accomplishing the lessonís objective. In making this decision, the teacher thinks about three components necessary in planning an effective sequence of learning. What initial activities will:

* focus studentís attention on experiences related to the new idea or skill to be taught?

* confront existing knowledge of students? Start with a "key" question that involves them in an physical/mental activity which focuses their attention.

* encourage students to recall and relate previous knowledge to new knowledge?

* bring out and make public what the students now know, their prior knowledge?

* provide an opportunity for students to try out prior knowledge?

Focusing Attention and Confronting Existing Knowledge

As a classroom lesson begins, studentsí minds are in different places. They may be thinking about what they are going to do during tonight, eat for lunch, or about a test later that day. When studentsí attention are focused on the intended lesson objective, greater learning will be likely to occur. The first few minutes of any lesson are important. Sensory information is held in the studentís memory for less than one second before the mind decides what to hold and what to forget. Most sensory information is not perceived by the student, it is forgotten. If the teacher does not help a student focus on the lessonís key ideas and skills the student may not obtain information relevant to the meaningful perception and later construction of the ideas into knowledge. This is necessary to help students connect the lessonís activities to their prior knowledge. The studentís attention will always focus on something. The teacher is responsible for focusing it on the key idea of the lesson.

Students attention can be focused in many ways. Student performed or demonstrated discrepant events are effective at this point in the lesson. For example, to focus studentsí attention on temperature, the teacher can ask students to touch different objects and describe how warm they feel. The teacher might also use a game, verbal statements of procedure, thinking aloud, a demonstration, or a problem situation to focus studentsí attention. Such activities can be omitted if students are already focused on the intended objectives and are ready to continue learning. This is the case when a concept is taught over several days during the week. In this case the teacher asks students to describe the activities they were involved in during previous days and involves them in discussing the outcomes of those activities.

Recall and Bring Out and Make Public What the Students Now Know

While it is possible to carry out a lesson without knowledge of a studentís prior knowledge, meaningful science learning will usually not result. Students who have not systematically experienced soil properties, for example, will not meaningfully understand concepts such as soil type and soil layering. In previous experiences students will have had to observe several examples of different soils and then classified them by common properties. These properties may have included size, color, shape, stickiness, and roughness to the touch. This activity may be related on class day to layers of soil the students discover while handling soil types, digging a hole or with a simulated example of soil layering students construct.

While students are actively participating in these experiences, an effective teacher will observe how they interact with the materials, the content of their discussion, and the meaning they begin to make of their explorations. This information will help the teacher decide how relevant the new ideas are to the students in view of their existing knowledge and the extent of teacher guidance needed in the next part of the lesson.

Relate Previous Learning to New Learning and Try Out Prior Knowledge

In order to help students remember what they have learned or transfer it to other things they know, it is important to use open-ended questions and examples of materials which call attention to their past experiences to try to help students recall them from their long-term memory. The teacher should help students retrieve as many related ideas or skills from long-term memory as possible. The retrieval of relevant information provides a knowledge structure into which new material learned can be placed. The retrieval also makes the studentís prior knowledge public. The student is made personally aware of her prior knowledge, in a non-threatening way, as are her peers and teacher. This is important. The student must check the ability of her prior knowledge to predict real world events. This will allow the student to determine the adequacy of the her view or suggest a possible better one to replace it. Unless the student confronts her misconceptions about the real world, she will keep them. She is likely to use the new knowledge on the next test but will forget it afterward since she is unable to transfer it to any new setting.

Recall from long-term memory alone is not a sufficient beginning for a lesson. Asking students, for example, to recall what happens when they have dropped different objects from a height is not sufficient to relate previous learning about gravity to new learning about this idea. However, encouraging students to explore gravity with a set of objects in free fall and on inclines of varying angles; make predictions about their speed, weights and time of falling motion; and record the results of tests could result is an effective first activity introducing the concept of gravity. A discussion of their experiences after students have worked with the objects will tie the activity more completely into their prior knowledge. Often one activity at the beginning of a lesson can accomplish all three purposes: focus, bring out, and relate old learning to new learning.

Invention Phase

Here the teacher should introduce a competing "scientific" conception to the students prior knowledge. The Invention should help students organize their information from the Exploration Phase. When planning the invention part of the lesson teachers make decisions on the following questions:

* How can the Exploration experiences be developed to focus on the basic idea or skill to be taught?

* How is the idea or skill best explained?

* How should the idea or skill be modeled or demonstrated?

* What strategies or techniques should be used to make sure all students understand it?

* What student practice is needed using the new knowledge?

* What would be a concise, brief closure?

This part of the lesson is more teacher guided. The teacher provides students with clear explanations and examples. Then completes this phase of the lesson with a closure in which the idea or skill being taught is defined and clearly stated.

Providing an Explanation

Explanation may be provided in a variety of ways including: discussion of findings resulting from the exploration activities, lecture, multimedia presentations, computer simulation, viewing a videotape, explaining sections of a textbook, and focused student activities. Since the short-term memory has a limited capacity, teachers must make certain that only important information is provided. When visuals and graphic organizers such as pictures, graphs, and demonstrations accompany verbal explanations more information can be stored efficiently. All aspects, conditions and contexts of a concept or experience with a generalization should be provided to students in order to concretely demonstrate its basic structure. An example of a concept might be "cold-blooded animals." A generalization might be "the lower the temperature of the surroundings, the slower the pace of the bodily functions of a cold-blooded animal ." Note taking guides often help make the organizational structure of the lesson more concrete when provided at the beginning of the invention phase. This is especially helpful when much of the explanation is done using lecture, textbook, or video presentation.

Providing Examples and Practice

Students need to see and practice clear examples of what the new ideas or skills represent so they may easily compare this new idea with their prior knowledge. One or more examples demonstrating the idea or skill should normally be presented at this point in the lesson. Sometimes this consists of demonstrating knowledge or skill through analogies or using working models. It also could involve taking the students through a step-by-step process. The more ways in which an idea or skill can be modeled for students, the more meaningful it will be to them (Clarke, 1990). The teacher should help the students distinguish between the variety of alternative conceptions possible.

An example of the concept of "cold-blooded animal " should involve students in experiences in which these animals take on the temperature of their surroundings, a range of cold-blooded animal types is observed, and the range of temperatures where these animals can function effectively is noted. To learn the generalization, "the lower the temperature of the surroundings, the slower the pace of the bodily functions of a cold-blooded animal", the students should be asked to make predictions and testing out hypotheses about the breathing rate of an animal as the temperature is reduced. This could be done through simulated data or by placing a small goldfish in a jar of water, adding an ice cube, counting the gill slit movements for a short intervals of 10 seconds, and measuring the temperature of the water with a thermometer. Communicating and discussing the results of predictions should be done in small groups and in whole class meetings.

An analogy may used in the following example during an investigation of simple electric circuits. The teacher uses a water pipe analogy when asking students to investigate simple electric circuits saying that when water flows into a pipe, its flow at the end will be determined by what happens to it inside the pipe. This analogy can cause many problems. Remember to carefully point out the limitations of the analogy or model. Prior knowledge here can interfere with new learning. Friction in the water pipe does not represent electrical resistance. The teacher should provide a series of examples on a worksheet in which students will predict whether different circuit designs will light a bulb. This would be followed by students checking their predictions through constructing real electric circuits, trying them out with batteries and wires, and observing the results of their trials. A discussion of results and of the patterns discovered should follow. In this activity, the analogy provides an organizational structure and a focus to help students see patterns in the examples given. The worksheet provides them with clear examples of the main idea of the lesson -- open and closed circuits. For a more complete description of teaching with analogies see Appendix 2.

Closure

It is important to plan activities to make certain that students have a clear description of the idea or skill they have been working with. An teacher should accomplish this at the end of the invention by using one of the following strategies. A clear description may be accomplished by stating the idea in a clear form to the students, asking students to state the main idea of the lesson orally or in writing the idea, or asking the students to demonstrate the skill.

Expansion Phase

The Expansion is perhaps the most important, but most overlooked, part of the lesson in traditional teaching. The goal is to help students finish restructuring old beliefs, old knowledge structures. After the Invention, or explanation, part of the lesson it is important to help students apply and transfer the new idea to new situations. This practice will help students retrieve it from their memory when they need to do so. This learning phase will require some time. The teacher must decide how to provide the practice necessary for accomplishing transfer into long-term memory. The teacher should stress the importance of thinking and talking about the significance of the experiences. The teacher should act as the mediator between the students prior knowledge and the scientific view of the new idea. Types of practice include manipulative activities, paper-and-pencil problems, question-and-answer discussions, field trips, games, computer simulations, or a return to the confrontation met in the Exploration Phase.

Practice Activities

At first, student practice of an idea or skill should be guided by the teacher. This enables them to receive feedback which tells them when they are accurate and successful. Without such guidance, students might practice errors, creating misconceptions which will require a great amount of effort to unlearn. Concrete or computer simulation activities should be used for practice. For example, students can be shown an example of a parallel electrical circuit. Then, they can be asked to find out which bulbs will light using this circuit. Or, the teacher could demonstrate a problem circuit and ask "What is wrong with this circuit?". These activities let the teacher know how accurately the students understand the lesson objective -- the idea or skill taught. The teacher can decide whether to remediate at this point or to move on. An important part of this practice includes asking students to explain their answers and describe their evidence for making the explanation, whether correct or incorrect.

At this point in the lesson, the teacher must decide whether the students have sufficient experience with the new idea to transfer it to a new context. Observation of student practice performance allows the teacher to decide which students are ready to move on to an application activity and which students need more practice or even reteaching.

Application and Transfer Activities

In order for an idea or skill to be remembered and used automatically from the long-term memory, sufficient application and transfer is needed, spaced out over time and in different contexts. After students perform the new skill or use the new idea in the classroom context, they are ready to transfer the new ideas to different situations and times. Often, this step is omitted in traditional courses because students have given some evidence of recall learning of the new idea earlier in the lesson. This amount of evidence is thought to be sufficient. However, students need extended experience in using the new idea in a new context over a period of time before an idea or skill can be stabilized in the long-term memory (Perkins, 1991). An example of practicing a new idea in another situation occurs when a teacher follows up the circuit activities described above by having students investigate the inside simple electrically wired devices and circuit diagrams to determine what types of circuits are used or to draw the possible electrical wiring for a room in a house.

Giving A Summary

Following the expansion activities a brief summary of the lesson should be given. The summary should include sequence the important ideas and events experienced in the lesson. Students can be asked to summarize or the teacher can give the summary.

Learning Cycle: Limitations

The learning cycle approach is best used as part of an pedagogical program that also stresses learning for all students, effectively uses cooperative learning groups and evaluates and rewards development of thinking skills such as critical thinking, creativity, development of self-worth, self-reliance, and respect for the opinions of others. In order for conceptual restructuring to occur and for meaningful learning to result from a learning cycle strategy, there are several prerequisites that need to be fulfilled.

First, change in an idea or skill should not be too great. Students should be challenged but not overwhelmed.

Second, relate lesson content to the background experiences of the students. This will help create a mental structure to which the new idea or skill can be tied. This is important if the new idea or skill is to be easily retrievable from long-term memory.

Third, use many concrete examples should be used in real situations during a learning cycle. Technology should be very helpful here.

Fourth, provide students with opportunities to work through practice situations using real or simulated actions. Learning should usually take place in cooperative learning groups.

Fifth, give students time to reflect, make mistakes, and form the new ideas or skills.

Sixth, teaching using the learning cycle requires less coverage of content but increased understanding of basic concepts. The alternative is to teach using traditional procedures which fosters memorization and a greater coverage of content in much less depth.

Seventh, using the learning cycle requires that the instructor select only those concepts which are basic to understanding the principle or theory. If time is a problem, it is possible to teach the other less important concepts in a more traditional style with some increased understanding.

Eighth, addressing all phases of the learning cycle is required in the order listed. Deleting a phase will create significantly less meaningful learning.

Other prerequisites may exist in various situations but these eight are always essential. While most students benefit from use of the learning cycle, gifted students require less dependence on use of the learning cycle and more open general inquiry activities for conceptual reconstruction to take place. The learning cycle may be planned to teach different types of objectives. Teaching a thinking skill, concept, generalization, or a theory will require the learning cycle to include different learning activities. For instance generalizations require an investigative set of activities starting with an hypothesis and testing in the Exploration and leading to verification of the hypothesis in different contexts during the Expansion phase.

Summary

The following points summarize the learning cycle. To accomplish meaningful learning:

1. Most of your students need a learning sequence different from traditional methods used to recall facts of science.

2. The worthwhile objectives (concepts, generalizations, theory, thinking skills, or dispositions) in the science topics you teach require a strategy of instruction different from traditional classroom presentation. Identify these topics in advance and plan lessons using the learning cycle.

3. The learning cycle consists of Exploration, Invention, and Expansion (EIE). Each phase must be experienced by the student in the order described.

4. A learning cycle must be planned for a specific idea or skill. Do not mix several important concepts or generalizations in a single learning cycle.

5. Demonstrate a questioning and reflecting attitude towards the content you teach. Generate hypotheses, examine alternative explanations and encourage your students to do the same. Ask students: What do you know about....? Why do you think....? How do you explain....? What evidence do you have? Reward appropriate responses from your students.

References

Anderson, R. (1977). The notion of schemata and educational enterprise: General discussion of the conference. In R. Anderson, R. Spiro, & W. Montague, (Eds.), Schooling and the acquisition of knowledge. Hillsdale, NJ: Erlbaum, 415-431.

Campbell, D. (1974). Evolutionary epistemology. In P. Schilpp (Ed.), The philosophy of Karl Popper. La Salle, IL: Open Court, 413-463.

Carey, S. (1986). Cognitive science and science education. American Psychologist. 41(10), 1123-1130.

Champagne, A., Gunstone, R. & Klopfer, L. (1985). Instructional consequences of studentsí knowledge about physical phenomena. Cognitive structure and conceptual change. L. West and A. Pines (Eds.). New York: Academic Press.

Champagne, A., Gunstone, R. & Klopfer, L. (1983). Naive knowledge and science learning. Research in Science and Technological Education, 1(2), 173-183.

Chi, M., Feltovich, P. & Glaser, R. (1981). Categorization and representation of physics problems by experts and novices. Cognitive Science, 5, 121-152.

Clarke, J. H. (1990). Patterns of thinking, integrating learning skills in content teaching. Boston: Allyn and Bacon.

Clark, C. & Peterson, P. (1987). Teachersí thought processes. Handbook of research on teaching, 3rd ed. M. Wittrock, (Ed.). NY: Macmillan, 225-296.

Collins, A. (1986). A sample dialogue based on a theory of inquiry teaching (Tech. Rep. No. 367). Champaign: IL. University of Illinois, Center for the Study of Reading.

Dillon, R. F. and Sternberg, R. J. (1986) Cognition and instruction. Boston: Academic Press.

Driver, R. (1986a). Children learning in science project. Leeds, UK: The University of Leeds.

Driver, R. (1986b). The pupil as scientist. Philadelphia, PA: Open University Press.

Duschl, R. A. (1990). Restructuring science education. New York:Teachers College Press, 30-80.

Gelman, R. & Baillargeon, R. (1983). A review of some Piagetian concepts. In P. Mussen (Ed.), Manual of child psychology (4th ed.): Vol. 3. Cognitive development. J. Flavell & E. Markman, (Eds.), NY: Wiley, 167-230.

Harlen, W. (1985) Teaching and learning primary science. New York: Teachers College Press.

Johnson, M. (1987). The body in the mind: The bodily basis of meaning, imagination, and reason. Chicago: The University of Chicago Press.

Karplus, R. (1979) Teaching for the development of reasoning. In A.E. Lawson (Ed.), 1980 AETS yearbook: The psychology of teaching for thinking and creativity. Columbus, Ohio: ERIC/SMEAC.

Lawson, A. E., Abraham, M. R. & Renner, J. W. (1989) A theory of instruction: Using the learning cycle to teach concepts and thinking skills. Atlanta: National Association for Research in Science Teaching, Monograph #1.

Mandler, J. (1983). Representation. P. Mussen (Ed.), Manual of child psychology, 4th ed.: Vol. 3. Cognitive development. J. Flavell & E. Markman (Eds.), NY: Wiley, 420-494.

Nussbaum, J., & Novick, S. (1982). Alternative frameworks, conceptual conflict and accommodation: Toward a principled teaching strategy. Instructional Science, 11, 183-200.

Osborne R.& Freyberg, P. (1985). Learning in science. Auckland, NZ: Heinemann Publishers.

Perkins, D. & Salomon, G. (1991). Teaching for transfer. Developing minds: A resource book for teaching thinking. D. Costa (Ed.). Alexandria, VA: Association for Supervision and Curriculum Development, 215-223.

Petrie, H. (1981). The dilemma of inquiry and learning. Chicago: University of Chicago Press.

Piaget, J. Forward to Hans G. Furth. (1969) Piaget and knowledge: Theoretical foundations. Englewood Cliffs, N.J.: Prentice Hall, vi.

Piaget, J. (1971). Biology and knowledge. trans. B. Walsh. Chicago: University of Chicago Press.

Posner, G. Strike, K., Hewson, P., & Gertzog, W. (1982). Accommodation of a scientific conception: Toward a theory of conceptual change. Science Education, 6(2), 211-227.

Roth, K. Anderson, C. & Smith, E/ (1986, February). Curriculum materials, teacher talk, and student learning: Case studies in fifth-grade science teaching. East Lansing, MI: Michigan State University, The Institute for Research on Teaching.

Rumelhart, D. & Norman, D. (1981). Accretion, tuning, and restructuring: Three modes of learning. J. Cotton & R. Klatzky (Eds.), Semantic factors in cognition, Hillsdale, NJ: Erlbaum, 37-60.

Saunders, W. (1992). The constructivist perspective: Implications for teaching strategies for science. School Science and Mathematics, 92(3).

Smith, E.(1990). Implications of teachers conceptions of science teaching and learning. In M. B. Rowe, The process of knowing, Washington D.C.: National Science Teachers Association.

Smith, E. & Anderson, C. (1984). The planning and teaching of intermediate science: Final report. East Lansing, MI: Michigan State University, Institute for Research on Teaching.

Sunal, D.W., (1994). Forest, Land, and Water: Understanding Our Natural Resources, Washington, D.C.:United States Forest Service.

Sunal, D., & Sunal C., (1994). Forest community dynamics, Science and Children, 29 (8).

Sunal, D., & Sunal C. S., (1991). Backyard aesthetics. Science Scope, 15(1), 25-29.

Sunal, D., and Sunal. C. S. (1991). Tree growth rings; what they tell us. Science Activities, 28(2), 19-26.

Tobin, K. Briscoe, C. & Holman, J. (1990). Overcoming constraints to effective elementary science teaching. Science Education. 74(4), 409-420.

Vygotsky, L. (1962). Thought and language. E. Hanfmann & G. Vaker (Trans.) Cambridge, MA: M.I.T. Press.

West, L. & Pines, L. (Eds.). (1985). Cognitive structure and conceptual change. New York: Academic Press.

Yager, R. (1991). The constructivist learning model: Towards real reform in science education. Science Teacher.

Science Knowledge

Methodological Conceptual

__________________________________|_____________________________________

Searching for Patterns and Theory (and schemata)

Relationships among

Generalizations - "Seeing that"

Searching for Patterns and Generalizations

Relationships among Concepts

Categorizing and Defining Concepts

Observations - "Seeing as" Facts

_______________________________________________________________________

Figure 1: Types of Science Knowledge (See Duschl, Restructuring Science Education)

___________________________________________________________

POND

 

 

(Seeing That)

Ecosystems

 

(Searching for Patterns)

 

 

Food Webs

 

 

 

Food Chains

 

(Categorizing and Defining)

 

 

Breeding Mosquitoes Small Predators Types of Fish Types of Plants

 

(Seeing As)

 

Itchy Mosquito Bites Seeing a Water Watching a Picking Apart a

Spider Skimming Sunfish Jump Pod From a

Along a Pondís in the Water Cattail

Surface

___________________________________________________________

Figure 2: Examples of the knowledge representations for the knowledge structure "pond". The arrows suggest some of the relationships found in this knowledge structure. Actually, many more could be drawn in. Every part of the structure is related to every other part in some way.

 

 

 

 

Middle School Student Beliefs About the World

__________________________________________________________

Science Sample Alternative Conception

Area

__________________________________________________________

Physical Science

Light Magnifying glasses make light bigger.

Electricity Electricity is used up when it passes through a light bulb.

Magnetism A compass needle points in the direction you are going.

Heat Heat and cold are two substances.

Temperature Temperature relates to an objectís size.

Force Force, pressure, and energy are the same thing.

Motion Constant motion requires a constant force.

Matter Molecules expand when matter is heated.

Conservation Sugar disappears when dissolved.

Earth Science

Earth Thrown objects may fall off the earth when dropped in the Southern Hemisphere.

Prehistoric Life Dinosaurs and "cavemen" lived at the same time.

Rocks Rocks must be heavy.

Soil Soil must always have been in its present form.

Rain Empty clouds are refilled by the ocean or the sun boils the ocean to create water vapor.

Oceans Oceans are so large they never change or can be changed by humans.

Seasons Seasons are caused by the Earthís distance from the sun.

Night Day and night are caused by the sun going around the earth or the earthís revolution around the sun.

Moon Different countries see different phases of the moon on the same day.

Solar System The solar system includes everything in the universe.

Planets Planets cannot be seen with the naked eye or appear to the naked eye as small disks.

Stars Stars are all at the same distance.

Zodiac Astrology (location of the planets in the stars) is able to predict the future.

Sun The sun is directly overhead at noon.

Biological Science

Fruits A tomato is not a fruit.

Plants Plants need fertilizer for food.

Animals Acquired characteristics can be inherited.

Osmosis Fluids move freely in and out of cells no matter what type or kind of material is involved.

Amino Acids Amino acids come from the cytoplasm of a cell.

Chlorophyll When part a leaf looses its green color, that part of the plant is dead.

__________________________________________________________________________

Figure 3: Sample of alternative conceptions middle school students bring to the science classroom

High School Student Beliefs About the World

__________________________________________________________

Physical Science - Specific misconceptions and altering teaching strategies

Force and motion

1. Misconceptions

a. Force and pressure and energy are the same thing

b. Constant motion requires a constant force

c. The harder your push it, will cause any object to move fastest

d. If an object isn't moving, there are no forces on it

2. Strategies

a. Allow students to expose and articulate misconceptions

b. Remember students always have their own personal theories. Students need to construct mental representations of alternative ideas presented.

c. Challenge studentís ideas with real world or mental experiences. Change in ideas will be slow, but the result is long-term change.

d. Allow students to reflect on planned experiences in class

e. Maintain good classroom atmosphere for good discussion

f. Allow students to predict experiments' outcomes. Have students consider

many interpretations or possibilities.

g. Teach the ideas conceptually and quantitatively through narrative discussion. Use various materials and situations when teaching one concept. The teacher should take on the role of motivator, facilitator, diagnostician, guide, innovator, experimenter and/or researcher.

h. Use meaningful and correct language

i. use appropriate models and analogies always explaining analogy context, use and limitations of comparison. Illustrate reversible processes. Focus on steady-state conditions.

j. Change students' ideas by demonstrating discrepant events

k. Explain and demonstrate the terms force, mass, pressure, speed and direction

Gaseous states

1. Misconceptions

a. Air molecules motionless

b. Air molecules expand

c. Air is often personified by students

d. Compressed air is considered heaped up or shriveled

e. Confuse volume and

f. Air can't be heated

g. Gases can't be heated

h. Gases exert force in only one direction

i. The atmosphere exerts a pressure only on a surface

j. Nature abhors a vacuum

k. Air sucks things up

l. Pressure is density

2. Strategies

a-j above plus

k. Explain and demonstrate the term pressure

l. Study air in motion first, then study motionless air

m. Help students to consider the characteristics of the outside of a container and the inside characteristics.

Matter in the gaseous phase

1. Misconceptions

a. There is no space between gas particles.

b. Air particles/molecules don't have intrinsic motion.

c. Non-physical factors may create force and motion.

(1) Animism

(2) Natural place of the substance, air exists in atmosphere

(3) Partial vacuum is does not exist, must be vacuum or normal air

2. Strategies

a-k above plus

k. Explain and demonstrate the terms force, pressure, density, speed and direction

l. Explain and demonstrate the origin and effects of pressure

Mathematics - Specific misconceptions and altering strategies

Ratio and probability

1. Misconceptions

a. Ratio in a physical event is determined by addition or subtraction, eg.4 is to 6 as 6 is to 8

b. All events must show change for a variable to have an effect

2. Strategies

a-k above plus

k. Explain and demonstrate the terms proportion, ratio, and probability

l. Explain and demonstrate the real world origin and effects of proportion, ratio, and probability

Biological Science - Specific misconceptions and altering strategies

Osmosis

1. Misconceptions

a. Do not understand the term concentration.

b. Hydrostatic potential is not understood.

c. Insist on an observable movement of solutions.

d. Membranes can't be semipermeable.

e. Solvents always move, but solutes never move.

2. Strategies

Use more experiments and drawings to counteract misconceptions.

More interactive discussion is also needed.

Amino Acids

1. Misconceptions

a. Amino acids, not enzymes, are products of translation.

b. Amino acids come from the cytoplasm.

2. Strategies

Consider the following four learning problem types: word association, instantiation, role conflict, and knowledge gap of students.

__________________________________________________________________

Figure 3: Sample of alternative conceptions high school students bring to the science classroom

ASPECTS OF STUDENTS' PRIOR KNOWLEDGE ABOUT HEAT

TO WATCH FOR

(This is an example of misconceptions which can be found in any science topic area - for example nutrition, environment, energy, physical and chemical change, etc.)

Students may hold the alternative view that:

1. "Heat " and "temperature" can be used synonymously - some students may think that these words have the same meaning or that more heat means higher temperature.

2. The sensation of coldness to due to transfer of cold towards the body - the sensation of hotness is also due to heat transfer towards the body,.

3. Heat and cold seen as opposite, fluid materials - some students use the word "heat" as a noun and write about it as though it flows into and out of objects. This may reflect little more than customary use of language. On the other hand it may reflect an underlying conception of heat as "stuff". This conflicts with accepted view of heat as energy in the process of transfer and may make it more difficult for students to differentiate at a later stage between heat and the internal energy of possessed by matter. Many students refer to cold and heat as though they are opposite substances.

4. Some substances are 'naturally' colder than others - the idea that substances in thermal contact are at the same temperature is not understood by some students. They suggest that substances have a "natural' temperature (e.g. metal is naturally colder than plastic).

5. There are no degrees of conductivity: students appear to think that either an object conducts heat (like metal) or it does not (like wood).

6. Metals have a greater capacity for heat than other materials: because metals feel cold students think that metals draw heat towards them, or naturally hold heat more effectively.

7. Particles of matter have macroscopic attributes: students may think that as heat is transferred to a substance, constituent particles expand, or melt.

8. Substances have "natural" melting and boiling points: the fact that a substance based on some observable property has reached the"natural" temperature at which melting occurs may be a sufficient explanation for some students (e.g. wax melts at a low temperature because it is soft).

9. Change of state occurs over a range of temperatures: despite identifying a melting point correctly from a graph many students suggest that melting would occur over a temperature range. Everyday experience may be confusing here, because rarely are substances which are observed melting or boiling maintained at uniform temperatures.

_______________________________________________________________________

Figure 4: Aspects of studentsí prior knowledge about heat to watch for (modified from Driver, 1986a)

 

Methods for Restructuring Studentsí Conceptions

___________________________________________________________________

Broaden the range of application of a conception

Differentiate a conception

Build experiential bridges to a new conception

Relate and update prior knowledge to new conceptual problems

Import a different model or analogy

Progressively shape a conception

Construct an alternative conception

_______________________________________________________________________

Figure 5: Methods for Restructuring Studentsí Conceptions

 

SUGGESTIONS FOR TEACHING AND LEARNING

USING STUDENTSí PRIOR KNOWLEDGE ABOUT HEAT

A. How can we make use of what we know about students' personal knowledge about science concepts (misconceptions)?

1. First, we can encourage students to talk about their ideas either in small groups. This may help learning in a number of ways:

a. It helps students to be aware of their own ideas. When students talk through their ideas they can often see the limitations and problems in themselves.

b. Students may also appreciate that different people can think differently about the same things. Appreciating a different point of view without necessarily believing it requires less egocentrism and some imagination.

2. When students have expressed their own ideas, learning activities should be devised to test out a variety of their ideas and theories.

If the science experience is to encourage the development of students' thinking then it is important that the alternative theories to be tested are their own rather than ones generated by the teacher.

B. What experiences may be helpful in developing students' ideas on the specific topic of heat?

In order to move towards more effective views of heat transfer and change of state, students need to learn to differentiate between sensory experience and scientific fact. This includes:

1. Experiences which establish that different objects in thermal contact with one another are at the same temperature (despite the difference in how they feel).

2. Experiences which help students to make the distinction conceptually between temperature and heat.

3. Student opportunities to explain the transfer of heat and the change of state in the real world.

4. Spending more time considering what is happening at a descriptive level when a range of substances are heated and a change of state occurs.

It is useful to study processes in reverse: heating and cooling, evaporation and condensation, conduction of heat towards the body and away from it. What may appear to be a simple reversal for us may be far from obvious to students.

C. How are sensory experiences and theory linked together?

There is an important relationship to be established between observations resulting from sensory experiences and the scientific interpretation of these observations. For instance, the different temperature sensations experienced on touching metal and wood can be interpreted using ideas about heat transfer and relative conductivities. Students, however, tend do fit the theory to their observations, and some students may reason that if the metal feels colder, it is because it is colder. Allowing students to test their alternative theories about their experiences may help them to make the connection between theory and observations, as will reference to observations and theory on the part of the teacher.

In practice, reality is much more complex than the classroom. Students' personal knowledge is often more "realistic" than the idealized situations with which they are presented in science lessons!

Students need to understand that science idealizations are made by scientists in explaining phenomena, but they have to recognize which assumptions are appropriate in a given situation. For this reason, relating actual phenomena to the scientific model used to interpret them is important. It is useful to give students time to understand phenomena at a qualitative level before and during the introduction of quantitative ideas.

_______________________________________________________________________

Figure 6: Suggestions for teaching and learning using studentsí prior knowledge about heat (modified from Driver, 1986a)

 

 

Alternative Beliefs of Teaching and Learning

__________________________________________________________

__________________________________________________________

Figure 7: Suggestions for teaching and learning using studentsí prior knowledge about heat (modified from E. Smith, 1990 in Rowe, The Process of Knowing)

 

SUMMARY FOR TEACHING AND LEARNING

USING STUDENTSí PRIOR KNOWLEDGE

1. Before students experience any formal teaching about science concepts in the science classroom, they are likely to have formulated intuitive ideas about the concepts which enable them to explain and predict familiar phenomena to their own satisfaction. These intuitive ideas are reinforced by students' everyday use of language. Intuitive ideas may be context dependent students do not appear to have consistent frameworks which they use to interpret events. However, the persistence of some of these ideas is strong.

2. When students are presented with ideas in science lessons, they make them fit into their intuitive ideas, and the result may be a mix of classroom science and intuitive science.

3. When they meet formal science lessons in school, students have to actively modify and restructure their own ideas. This requires a willingness and effort on the part of the learner. If the ideas held by the students are to be taken into account, teaching cannot simply be viewed as the 'telling' or 'giving' of knowledge to passively sitting students. Teaching involves helping each student to construct for herself or himself, the accepted ideas. The starting point of a teaching sequence is then the intuitive ideas students bring with them. Use the learning cycle helps students restructure their ideas. The learning cycle fosters meaningful learning.

4. Having determined the prior know;edge held by students in a class, the role of the teacher then becomes that of prescriber and facilitator of the appropriate student learning activities. The professional ability of the teacher to make such decisions about the needs of the students, difficulty or level of the content, and the teaching sequence and strategy is of greater value in the teaching and learning process, then the textbook or other curriculum materials provided in the traditional classroom.

____________________________________________________________________________

Figure 8: Summary for teaching and learning using studentsí prior knowledge

 

 

Steps in Planning A Class Lesson Using the Learning Cycle for a New Idea or Thought Process (Thinking Skill/Algorithm)

________________________________________________________________________

The learning cycle sequence is not a blueprint for teaching, but a set of decision points that all teachers must address in the planning process if they are to adequately help students learn important ideas. Recognizing these decision points assists teachers in deciding to act in keeping with what is known about how learning takes place.

Exploration

* Attempt to confront existing knowledge of students. Start with a "key" question that involves them in an physical/mental activity which focuses their attention,

* Focus students attention on experiences related to the new idea or skill to be taught,

* Encourage students to recall and relate previous knowledge to new knowledge,

* Bring out and make public what the students now know, their prior knowledge, and

* Provide an opportunity for students to try out their prior knowledge in the new setting.

Invention

* Ask students to reflect on and discuss the results of Exploration activity to provide connections to focus idea of the lesson.

* Provide a clear explanation using multimedia and interacting with students where possible describing aspects, analogies, contexts, and uses.

* Provide clear examples or model the new skill.

* Provide student practice using the new knowledge

* Provide a concise brief closure.

Expansion

* Provide additional student practice activities if needed. Use personally relevant examples, not abstract, repetitive practice.

* Provide student application activities in new relevant contexts. Multiple activities should transfer the new knowledge to increasingly real world situations and involve more relevant to students personal and professional needs.

* Provide a summary which highlights and focuses attention on the experiences where the new knowledge was learned

_______________________________________________________________________

Figure 10: Steps in planning a Learning Cycle lesson

 

The Learning Cycle

Teaching for Conceptual Change

_____________________________________________________________________________

Exploration Phase

Purposes:

To provide background experience and learning through studentís' own actions and reactions and

To introduce aspects and values of a new idea -- concept, variable, generalization or thinking skill (enhances assimilation).

Exploration allows students to confront and make evident their own thinking/representation of the idea or skill to be learned.

Characteristics include:

1. Encourages learning through studentís own inquiry and focuses interest

2. Involves minimal guidance or expectation on the teacher's part

3. Often provides an experience which confronts students old way of thinking

4. Begins with a well planned "key" question from the teacher

5. Involves students working in cooperative learning groups

6. Encourages observation of natural world

7. Raises questions for the students

8. Provides for student action with hands-on materials, collecting and organizing data

9. Encourages students mental actions in selecting resources discussion and debate

10. Encourages trying out prior ideas, suspending judgment, predicting, hypothesizing and testing

11. Provides students with adequate time to relate prior knowledge with new idea

12. Allows students to know the purpose and objective of the lesson

13. Allows teacher to know present student understanding in the lesson objective area

Invention Phase

Purpose:

To explain an alternative (new) idea or situation leading students to mentally construct new patterns of reasoning (encourages accommodation).

Invention builds on the Exploration by guiding the students through a more direct teaching format, to experience and develop the concept or skill more fully or to a higher order.

Characteristics include:

1. Continues development of the new idea or skill (reasoning pattern) in students through teacher directed reflection and discussion of Exploration experience

2. Involves communication of information and ideas offering alternative ideas (solutions) for the confrontation

3. Allows learning from "explanation" which includes an interesting variety in teaching actions, multimedia and interactions with students describing aspects, ranges, contexts, and uses of the new idea or skill.

4. Introduces idea or skill introduced in a structured manner through additional student experience using a variety of demonstrations, analogies, audio-visual materials, sense modalities, textbook readings, or other medium

5. Encourages students to develop as much of the new reasoning pattern as possible through providing one or more complete cycles of explanation, giving clear examples, modeling, and checking for understanding

6. Offers students time to question, try out and practice the new alternative explanation

7. Ends with a concise closure describing the main idea or skill introduced

Expansion Phase

Purpose:

To apply and transfer the new reasoning pattern (idea or skill) to other example(s), situations and contexts extending the range of applicability to help stabilize (make permanent) the new knowledge

Expansion activities allow studentís to practice, apply, and transfer the idea or skill just explained in the Invention.

Characteristics include:

1. Provides for learning by additional practice where students use labels, definitions, explanations, and skills in new, but similar situations. It is important to use personally relevant examples, not abstract, repetitive practice.

2. Provides additional time and experiences for students to ask questions, observe, record, use explanations, make decisions, and design experiments to apply the new idea or skill in new, but similar situations.

3. Encourages transfer of the new knowledge to various real world contexts and other times different from where the new idea or skill was explained.

4. Relates student activities to personally and professionally relevant settings, thus, helping complete abstraction from classroom and textbook concrete examples.

5. Ends with a lesson summary which highlights and focuses attention on the experiences where the new knowledge was learned

_____________________________________________________________________________

Note: If a phase is eliminated or all students are expected to demonstrate specific accomplishments after each one, then the overall effectiveness of the learning cycle will be compromised.

_____________________________________________________________________________

Figure 11: Model characteristics of each phase of a Learning Cycle

 

 

 

Learning Cycle Lesson Plan Format

_____________________________________________________________________________

The learning cycle lesson plan should contain the following sections.

Lesson Information

Key Idea or title

Goal

Prerequisite skills and concepts

Lesson Activities:

1. Exploration Phase

Objectives

Materials

Introduction to Lesson

Procedure: student activities which:

confront prior knowledge

relate previous knowledge to new idea

try out prior knowledge

Evaluation - monitor and diagnose student needs

2. Invention Phase

Objectives

Materials

Procedure: teacher/students activities which

provide explanations

provide examples

provide practice

provide closure

Evaluation - monitor and diagnose student needs

3. Expansion Phase

Objectives

Materials

Procedure: Students activities which:

provide additional practice

provide application and transfer

provide lesson summary

Evaluation - student understanding

___________________________________________________________________________

Figure 12: Learning Cycle lesson plan format

Appendix 1

LESSON FRAMEWORK DESIGNS FOR CONCEPTUAL CHANGE

Consider how a learning model can assist in the planning of a specific lesson or set of lessons designed to modify student's intuitive ideas. In doing so we face a problem of our own making: to be useful, our discussion needs to propose particular sequences of classroom activities, yet our theoretical perspective suggests that these sequences cannot be planned until we have found out just what it is that the class already knows.

Several frameworks or models for the planning of science lessons designed to change student's views have been proposed in recent years. Possible templates for science teaching sequences have been suggested by a number of researchers. These frameworks are similar in that they center on a strategy and a sequence which involves experience, interpretation, and elaboration. See Table 1 for a summary. They all fit under the general name of the learning cycle (Karplus, 1979).

A review some of the teaching sequences that have been proposed over the past few years is provided below.

Renner. Renner (1982) described the most common practice of teachers is to attempt to pass on to their pupils a mastery over content as the content is envisaged by the teacher. The theory of learning underlying this approach is, first, that the material to be taught can be given to the learner as information; second, that it should then be verified by the learner through observation; and finally, that the information should be applied in some way to "settle it in". The first stage, informing or telling, is usually attempted through the teacher's opening statements or as the introduction to a soĖcalled "experiment". This subsequent activity is not an experiment in the investigatory sense, however, but merely a verification or demonstration since both pupils and the teacher already know the expected outcome. The final stage, in this typical science sequenceĖĖapplication of knowledgeĖĖusually involves answering questions and solving quantitative or mathematical problems from a textbook in preparation for a test of some kind.

Renner's analogy for this entire process is that of a guided tour where the guide, the teacher, points out all the sights to be observed and the learner is discouraged from taking any detour that, in the guide's view, is not productive.

If we accept that each of us must develop the understandings we have about a concept for ourselves, then Renner suggests an alternative teaching model as more appropriate.

1) His initial concern is with pupils gaining experience and this becomes the first stage of his teaching model. Learners are provided with suitable experiences in order to create for themselves what is to be learned.

2) In the second stage, the learner is introduced to some appropriatelyĖspecific terminology in relation to the phenomenon being investigated. The teacher uses this to assist the learner to interpret what has been found.

3) In the third stage, the new ideas of the learner are meshed with existing knowledge in order to expand both that knowledge and the newly acquired idea. Additional experiences to help this elaboration process are an essential part of this stage. These experiences would have some of the attributes of experiments because the outcomes would not be known even though the pupils know the concept that is the subject of investigation.

In summary, Renner's view is that much conventional science teaching is simply a training process which involves telling, confirming and practicing. Its limitations are obvious. From the generative learning point of view, it omits the vital activities which involve originating experiences, interpretation and elaboration.

Karplus. Some other models which have been proposed also reflect a similar viewpoint to Renner's in that they demonstrate a real concern for the cognitive development of the learner. One such model was proposed by Karplus (1977) and he, like Renner, has been somewhat influenced by the Piagetian theories of development. Karplus argues that science learning should be a process of selfĖregulation in which the learner forms new reasoning patterns. These will result from reflection, after the pupil interacts with phenomena and with the ideas of others. Karplus also proposes a threeĖphase learning cycle.

1) The first phase is one of exploration in which pupils learn through their own actions and reactions with minimal guidance, while the teacher anticipates few specific accomplishments. The learners are expected to raise questions that they cannot answer with their present ideas or reasoning patterns.

2) In the second phase of the Karplus model, the concept is introduced and explained. Here the teacher is more active, and learning is achieved by explanation.

3) Finally, in the application phase, the concept is applied to new situations and its range of applicability is extended. Learning is achieved by repetition and practice so that new ideas and ways of thinking have time to stabilize.

An interesting analysis of the use of this particular learning cycle within topic is provided by Smith and Lott (1983).

Driver. An idea or framework will not be rejected until there is something adequate and reliable to replace it with. Pupils can be given experiences which conflict with their expectations, but these experiences do not of themselves help the pupils to reconstruct an alternative view of the system. Driver (1986b) proposes a sequence of instruction involving;

1) Evidence or data should be presented so that the pupil has an opportunity to discover the new framework as an interpretive framework, constructed in the mind, and therefore has to be invented.

2) Many times students are left with an incomplete construction or none at all. The new ideas must also be presented by the teacher as inventions.

3) The pupils are then encouraged to see the value and power of the ideas by applying them in a range of activities. This will take the greatest amount of time, otherwise will cause students to memorize the new ideas.

Nussbaum and Novick. A similar threeĖstage model has been suggested by Nussbaum and Novick (1981). They sought to explain what happens as learners change their conceptions during instruction. Their strategy, in common with all of the models summarized here, is based on the principle that "science concept learning involves cognitive accommodation to an initiallyĖheld alternative framework". Or, as we would prefer to put it, the teaching task is to ascertain individual student's conceptions about science topics and to modify these towards the current scientific view.

1) To bring about cognitive accommodation, Nussbaum and Novick suggest that the first step is to expose the alternative framework. They note Ausubel's warning that "preconceptions are amazingly tenacious and resistant to extinction" (Ausubel, 1968), and accept that such preconceptions often interfere with the teacher's learning outcomes. Thus, Nussbaum and Novick propose that the first step in facilitating accommodation should be to ensure that every student is aware of his/her own preconceptions. To them, this is most easily achieved if some event can be devised which requires learners to make explicit their existing ideas in order to interpret it. Pupils are encouraged to describe their own views verbally and pictorially, and the teacher assists them to state these ideas clearly, in order to recognize what they can and cannot explain. Pupils are encouraged to debate the various views represented by all of their fellow learners, in order to better understand the features of each view.

2) Assuming that learner dissatisfaction with their existing ideas results from such activities, and the teacher provides additional experiences which will lead to further dissatisfaction, the conceptual conflict is likely to result. Nussbaum and Novick imply that this conflict must be sufficient to induce students to recognize that their existing views require modification.

3) Accommodation develops from pupils searching for a solution to their conflicting ideas. Hence, in the Nussbaum and Novick model, concept learning is achieved by exposing alternative frameworks creating conceptual conflict and encouraging cognitive accommodation.

Erickson. Erickson (1979) makes a parallel set of proposals.

1) The first stage of his model is the provision of a set of experiential maneuvers, which allow the learners to become familiar with a wide range of phenomena, so that they might expose a set of intuitive ideas or beliefs. In this stage, the activities are considered in sufficient depth to allow the learners to clarify their ideas and to develop confidence so that they may begin to make predictions.

2) The second stage contains anomaly maneuvers, involving the creation of situations that lead to unexpected outcomes. An element of uncertainty is introduced; the learner needs to restructure his/her views.

3) The third stage is a set of restructuring maneuvers to assist the learners in accommodating unexpected outcomes. Restructuring, in Ericksen's strategy, could be achieved by, for example, group discussions and teacher intervention.

Barnes. Barnes (1976) also contends that learners need to take a prominent part in the formulation of their own knowledge. To reduce the teacher's perceived control over knowledge, Barnes believes that students should work primarily in small groups. In practical terms he proposes the following sequence:

1) A focusing stage, in which the teacher, with the students, prepares the ground by presenting preliminary knowledge (which, we assume, includes "alternative frameworks" and "student's science"). When the attention of the class is fully focused on the topic, the teacher moves on to an

2) Exploratory stage, involving much discussion and other activities, including experimentation. Then in the

3) Reorganizing stage, the teacher reĖfocuses attention and tells the groups how they will be reporting back, and how long they have to prepare for it. Finally, in the

4) Public stage, the groups of learners present their findings to one another, and this leads to further discussion

Rowell and Dawson. A further model has been suggested by Rowell and Dawson (1983). This more explicitly focuses on the confrontation between student's science and scientists' science. They suggest the following sequence:

1) Through questioning, the teacher establishes the ideas which children bring to the problem situation. Conscious awareness of these ideas is of value to both the teacher and the children.

2) These ideas are accepted by the teacher as possible solutions.

3) Students are asked to retain their ideas, and the teacher states that he or she is going to put forward another possibility which the children will help in evaluating later.

4) The "new" idea is taught by linking it to a basic idea already held.

5) Once the new idea is available to students then the old ideas are recalled for comparison, with each other and with reality.

Rowell and Dawson believe that students are less threatened by this approach than some others, since both "old" and "new" ideas are the pupils' own in the sense that all are pooled knowledge. Assuming that old theories are rarely defeated by contrary evidence but only by better theories, they argue that the children with several ideas available to them are in the best possible situation to accept the scientist's one when it is tested against the others.

The Generative Learning Model (GLM). The GLM model proposed by Osbourne and Wittrock (1983) and summarized by Kyle and colleagues (1989) has four steps that closely parallel the Center's proposed model of learning and teaching:

1. In the preliminary step, before beginning any formalized instruction, teachers assess students' ideas and conceptual explanations;

2. In the focus step, the teacher provides experiences related to the particular concept that motivate the students to explore their level of conceptual understanding;

3. Next, the teacher helps students exchange points of view and challenges students to compare and contrast their ideas and support their viewpoints with evidence (the challenge stage); and

4. In the application stage, students use their newly refined conceptual understandings in familiar contexts.

The Riverina-Murray Model. The Riverina-Murray Institute of Higher Education (Boylan, 1988) presents a five-stage model of learning and teaching and learners must pass through as they develop a new level of conceptual understanding. The stages are:

1. The teacher identifies the learner's naive ideas about a selected concept;

2. Based on that information, the teacher selects events, situations and activities for the learner to explore;

3. The exploratory phase provides a practical base upon which the learner begins to develop a new understanding. The learner is encouraged to make the concept explicit and also is introduced to new language and symbols;

4. The learner organizes the new idea and establishes links with relevant prior knowledge; a new mental scheme emerges; and

5. She learner practices and applies the new idea in novel situations to consolidate the newly developed understanding.

The Hewson-Hewson Model. The Hewsons, after reviewing studies on science learning, summarize "key points in instructional strategies which help students overcome their naive, inappropriate conceptions" (Hewson and Hewson, 1988:607). Teachers must:

1. Diagnose students' thoughts on the topic at hand;

2. Provide an opportunity for students to clarify their own thoughts;

3. Directly contrast students' views and the desired view through teacher presentation or class discussion;

4. Immediately provide an opportunity for students to use the desired view to explain a phenomenon: and

5. Provide an immediate opportunity for students to apply their newly acquired understanding in novel situations.

The Lawson-Abraham Model. Anton Lawson (1988), Michael Abraham (1989), and colleagues (Lawson, Abraham, and Renner, 1989; Renner, 1986) long have advocated a three-step learning cycle. This is based on a three-step cycle first proposed by Atkin and Karplus (1962), who later used it in the innovative elementary science program, the Science Curriculum Improvement Study (SCIS).

1. Derived from Jean Piaget's developmental theory, the learning cycle approach first uses a laboratory experiment to expose students to the concept to be developed. Abraham calls this the exploration or gathering data phase.

2. Next, the students and/or teacher derive the concept from the data, usually a classroom discussion (the conceptual invention phase).

3. The final phase, expansion, gives the student the opportunity to explore the usefulness and application of the developing concept.

Lawson (1988) and others prefer to call the second phase "term or concept introduction" because they recognize that, while teachers can give students new terminology, ultimately the student must actively invent or generate the concept. Lawson has recently proposed that there are three kinds of learning cycles; descriptive, empirical-deductive and hypothetical deductive. The sequence of learning-teaching events is essentially the same in each.

Driver-Oldham Model. Driver and Oldham (1986) describe a constructivist teaching sequence used in the Children's Learning-in-Science Project. They suggest that it be viewed as a flexible outline because the demands of different conceptual areas and the time available for learning and teaching will vary.

1. In the orientation phase, students are motivated to learn the topic. In the elicitation phase, students make their ideas explicit through discussions, creation of posters, or writing.

2. In the restructuring phase, teacher and students clarify and exchange views through discussion; promote conceptual conflict through demonstrations; exchange ideas; and evaluate alternative ideas.

3. In the application phase, students use their new ideas in familiar and novel settings.

4. The review phase allows students to reflect on how their ideas have changed.

5. The model incorporates several aspects of technological problem-solving and decision-making notable evaluation of alternative ideas and reflection at the end of the learning sequence.

_____________________

Insert Table 1 here

______________________

Appendix 1 References

Abraham (1989). Research and Teaching: Research on instructional strategies. Journal of College Science Teaching 18(3),185-187.

Barnes, D. (1976). From communication to curriculum. Hammondsworth, UK: Penguin Books.

Boylan (1988). Enhancing learning in science. Research in Science and Technological education. 6(2), 205-217.

Driver, R. (1983). The pupil as scientist. Milton Keynes, UK: Open University.

Driver, R. and Oldham (1986). A constructivist approach to curriculum development in science. Studies in Science Education. 13,105-122.

Erickson, G. L. (1979). Children's conceptions of heat and temperature. Science Education, 63, 221Ė230.

Hewson and Hewson (1988). A appropriate conception of teaching science. Science Education. 72(5),597-614.

Karplus, R. (1977). Science teaching and the development of reasoning. Berkeley, CA: University of California.

Lawson, A. (1988). Student reasoning, concept acquisition, and a theory of science instruction. Journal of College Science Teaching. 17, 314-316.

Nussbaum, J. and Novick, J. (1981). An assessment of children's concepts to invent a model; a case study. School Science Review, 62, 221, 771Ė778.

Osbourne and Wittrock (1983). Learning science: A generative process. Science Education. 67(4), 489-508.

Renner, J. (1982). The power of purpose. Science Education, 66, 5, 709Ė716.

Rowell, J. A. and Dawson, C. J. (1983). Laboratory counter examples and the growth of understanding in science. European Journal of Science Education, 5(2), 203Ė215.

Table 1

CHANGING STUDENT IDEAS

A Variety of Learning Cycle Frameworks

Nussbaum and

Phase Renner Karplus Driver Novick

_____________________________________________________________________________ 1 Experiences Exploration Discovery Exposing

alternative frameworks

2 Interpretation Explanation Presentation Creating

conceptual

conflict

3 Exploration Application Application Encouraging

cognitive accommodation

____________________________________________________________________________

Rowell Osbourne

and and

Erickson Barnes Dawson Whittrock

GLM Model _____________________________________________________________________________

1 Experiential Focusing Establish Assess student

maneuvers initial ideas

ideas Focus activity

2 Anomaly Exploration Introduce Exchange

maneuvers new points of

ideas view

3 Restructuring Reorganizing Comparison Use

maneuvers of ideas ideas

4 Public

____________________________________________________________________________

Riverina Hewson Lawson Driver

and and and and

Murry Hewson Abraham Oldham _____________________________________________________________________________

1 Identify Diagnose Exploration Orientation

naive and

ideas motivation

Select events

2 Exploratory Opportunity to Conceptual Elicitation

activities clarify and invention of ideas

contrast

3 Organize Practice new Restructuring

ideas and idea ideas through

establish links exchange

4 Practice and Apply idea Expansion Application

apply new idea and review

_____________________________________________________________________________

Appendix 2

Using Metaphors, Models and Analogies in Teaching Science

Observation of instruction in many classrooms, suggests that use of models and analogies may produce as much good as harm, creating acceptable student understanding at the same time generating misconceptions and causing more confused learning. Research has identified the problems for student understanding caused by the inappropriate use of analogies. Research suggests that the use of a teaching strategy for the presentation of models, metaphors and analogies will enhance student understanding and reduce misconceptions. One of these is Glynnís (1991) model of Teaching-With-Analogies (TWA), a model developed from an analysis of science textbooks.

The Teaching Strategy

The idea familiar to the students will be labeled the analog model. The science idea to be learned will be called the concept.. Links between the analog model and concept, with shared and unshared attributes, are called mappings. While each step is important, the order in which the steps are used depends upon the teacher's style, the particular scientific concept, and the analogy being used. In its general form, the systematic approach for teaching with analogies is as follows:

Step 1--Introduce the concept to be learned (ie. through the exploration and the beginning of the invention phase of the learning cycle). Give a brief or full explanation depending on how the analogy is to be employed.

Step 2--Review with the students' the analogous situation. Introduce the analog model so that its familiarity to the students can be estimated by discussion and questioning.

Step 3--Identify the relevant features of the analog model. Explain the analog model and identify its relevant features at a depth appropriate to the students' familiarity with the analog model.

Step 4--Map out the similarities between the analog model and the concept. teacher and students both must identify the relevant features of the concept and link these with the corresponding features of the analog model.

Step 5--Indicate where the analogy breaks down. Note alternative conceptions that the students may be developing and known areas where the analog model and concept do not correspond. Point these out to the students to discourage incorrect conclusions about the concept from the analog model.

Step 6--Draw conclusions about the concept. Summarize the important aspects of the concept.

At Step 1, three approaches are possible. When the analogy is used as an advance organizer, the concept is introduced after the analogy. When the analogy is used to develop the concept, the concept should be taught in sufficient detail to make the analogy relevant. When the analogy is used as a revision, the concept is fully taught. Teachers can enhance analogical instruction by choosing an appropriate analogy before the lesson and carefully planning how it will be taught and used. Steps 2, 4, and 5 are the points where student understanding often fails to match the teacher's expectations.

Teaching with Analogies

It is generally recognized that analogies generate meaning through a constructivist pathway (Duit, 1991). Although students come to science with tenaciously held intuitive ideas and beliefs about science-related phenomena before they have experienced the relevant formal teaching, the students' ideas are often ignored by teachers; consequently, students derive meaning from an analogy that is often incompatible with the teacher's view. It is imperative that teacher and student hold a common view of the analog model before mapping begins. Thus, at Step 2, if the student visualizes the analog model in a different way that the teacher, it is no wonder that the student generates alternative conceptions. Teachers draw on a far richer knowledge base than do their students, and there may be distinct cultural and socioeconomic differences as well that can lead to misconceptions.

As an teacher becomes proficient in the use of this teaching sequence, he or she may unite Steps 3 and 4 as a single step. As relevant features of the analogy are identified (Step 3), they are often mapped immediately as the first of the shared attributes (Step 4). Our in-class observations show that student mapping of the shared attributes cannot be taken for granted. Additional shared attributes that were not immediately apparent became so as the analogy was discussed in class, and, on several occasions, weaker students made valuable contributions to the mappings that had been overlooked by more able students.

Post-lesson student interviews can be of value for examining unshared attributes. Every analogy breaks down somewhere, and many analogies employed in science are used for phenomena that are foreign to students. It is unreasonable to expect novices to make expert judgments on structures or functions that they cannot see or even visualize. Students reported that they were much more comfortable with their understanding after the teacher had identified the unshared attributes of the analogy. It is also expected that teachers may perform Steps 4 and 5 as a parallel exercise because, as students propose analog model-concept mappings, shared and unshared attributes will emerge side-by-side. Step 6 is necessary because it articulates what has been found by carefully relating the familiar to the unfamiliar.

An Example

Homeostasis is like a student walking up a descending escalator. The following account describes how an teacher might present this analogy using our systematic approach:

(Step 1) -- Homeostasis is the process by which living things balance input and output to maintain a constant internal environment. When input and output are balanced, the internal environment is in dynamic equilibrium. In this way, organisms actively maintain such things as temperature, water, O, CO, and blood glucose levels. As all living things are active, these items only remain constant because the amount taken in (being produced) equals the amount being consumed (removed).

Let's look at the maintenance of body temperature. Our body processes work best when our internal temperature is 37 degrees C. If our body temperature varies by more than about 3 degrees C in either direction, we can die.

(Step 2) -- Are you all familiar with escalators, the moving stairs that are found in many department stores? Imagine a student walking up an escalator that is moving down. What will happen?

(Step 3) -- If the student walks up the escalator at the same speed that the escalator moves down, she appears to an external observer to stand still. The student and the escalator are in equilibrium/ If she walks up faster than the escalator goes down, she slowly moves up, but if she walks slower than the escalator, she moves down.

In both cases, there is no equilibrium. Equilibrium can only be restored by altering the student's velocity so that it is the exact opposite of the escalator.

(Step 4) -- Normally, we lose heat by conduction to the air from our skin and lungs, which is like the escalator constantly moving downwards. Internal heat is continuously produced by cellular respiration, like the student walking upwards at a normal walking speed. When the rate of metabolic heat production equals the rate of heat loss to the air, temperature remains constant just as, to an external observer, the student appears to remain at one level even though she is walking up as the escalator moves down. (This is a state of equilibrium).

If we stand in sunlight or close to a heater, we gain extra heat, and this is analogous to the student walking faster. If our rate of heat loss to the air remained constant and nothing else changes, our temperature would rise, and, just as the student ends up at the top of the escalator, we would overheat and die. Normally, we would not overheat in this way because we begin to perspire, and as the sweat evaporates, we cool down. This is analogous to the student slowing down to maintain a constant level on the escalator. When we get too hot, we slow down to rest and restore equilibrium.

If we were left unprotected in an icy wind or cold water, we would lose heat much faster, as if the escalator moves down faster than the student walks up. Soon she will be a the bottom (death from hypothermia). If the cooling is not too severe, we can increase our muscular activity to produce extra heat and balance the loss, which would be like the student running up the escalator, since increased production balances greater loss.

(Step 5) -- The way this analogy was used, the top and bottom of the escalator represent high and low temperatures respectively. The analogy suggests that, provided the student walks up as fast as the escalator moves down, acceptable equilibrium is possible at any temperature (any level of the escalator). This is not so, however, because every homeothermic animal has an optimum temperature. Another factor that has been ignored is that, as body temperature rises, heat is lost faster to the air because there is a greater temperature difference. As body temperature falls, the rate of heat loss falls.

(Step 6) -- Equilibrium in living things is an active process involving balanced input and output, with the rates of input and output being equal but in opposite directions.

Summary

Presenting analogies with a planned teaching strategy has the potential to enhance student understanding of science concepts while reducing the incidence of misconceptions being formed. Effective teaching using analogies appears to contain at least three active steps: (1) ensuring that the teacher and students visualize the analog model congruently, (2) developing the shared attributes to plausibly elucidate the concept, and (3) clearly identifying unshared attributes for the students.

Appendix 2 References

Duit, R. (1991), On the role of analogies and metaphors in learning science, Science Education, (75), 649-672.

Glynn, S. (1991), Explaining science concepts: A teaching with analogies model. In S. Glynn, R. Yeany & B. Britton (Eds.) The psychology of learning science. pp. 219-240.

Harrison, A.G. & Treagust, D. F. (1993), Teaching with analogies: a case study in grade 10 optics. Journal of Research in Science Teaching , 30(10), 1291-1307.

Harrison, A.G. & Treagust, D. F. (1994), Science Analogies. The Science Teacher , April, 40-43.

Some Useful Tools for Teaching Science

Books and Reports

American Association for the Advancement of Science, (1993). Benchmarks for Scientific Literacy, New York: Oxford University Press

American Association for the Advancement of Science, (1993). Science for All Americans, New York: Oxford University Press (Oxford Univ. Press, Dept. EC, Madison Ave. N.Y.,10016, 1-800-230-3242)

Driver, R. (1986b). The pupil as scientist. Philadelphia, PA: Open University Press.

Duschl, R. A. (1990). Restructuring science education. New York: Teachers College Press.

Ellis, J.(1993). (Ed.) Information Technology and Science Education, Columbus Ohio: ERIC, AETS

Fensham, P., Gunstone, R., & White, R. (1994). The content of science, a constructivist approach to teaching and learning, Washington, DC: Falmer Press.

Gabel, D. (1994). Handbook of Research on Science Teaching and Learning, New York: Macmillan Publishing Co.

Hassard, J. (1992). Minds On Science, NY:Harper Collins Publishers.

Lawson, A. E., Abraham, M. R. & Renner, J. W. (1989) A theory of instruction: Using the learning cycle to teach concepts and thinking skills. Atlanta: National Association for Research in Science Teaching, Monograph #1.

National Center for Improving Science Education, (1991). The High Stakes of High School Science, Washington, DC: The Network Inc.

Novak, Misconceptions Research: Procedings from the 2nd international conference, v. 1-4.

Osborne R.& Freyberg, P. (1985). Learning in science. Auckland, NZ: Heinemann Publishers.

Rowe, M. B, (1990). The Process of Knowing, Washington, D.C.: National Science Teachers Association. (1-800-722-NSTA)

Shayer and Adey, Science of Science Teaching

Wright, E. and Govindarajan, G. (1992). Teaching With Scientific Conceptual Discrepancies, Manhattan, KS: Kansas State University. (C/O Emmett Wright, College of Education, Bluemont Hall, Kansas State University, Manhattan, KS 1-913-532-7838)

West, L. & Pines, L. (Eds.). (1985). Cognitive structure and conceptual change. New York: Academic Press.

Whitmer, J. (1992). Spreadsheets in Mathematics and Science Teaching, Bowling Green, OH: School Mathematics and Science Association.

Journal Articles

Abraham (1989). Research and Teaching: Research on instructional strategies. Journal of College Science Teaching 18(3),185-187.

Champagne, A., Gunstone, R. & Klopfer, L. (1983). Naive knowledge and science learning. Research in Science and Technological Education, 1(2), 173-183.

Duit, R. (1991), On the role of analogies and metaphors in learning science, Science Education, (75), 649-672.

Posner, G. Strike, K., Hewson, P., & Gertzog, W. (1982). Accommodation of a scientific conception: Toward a theory of conceptual change. Science Education, 6(2), 211-227.

Saunders, W. (1992). The constructivist perspective: Implications for teaching strategies for science. School Science and Mathematics, 92(3).

Sunal, C., Sunal, D., (1996, in press). Meaningful learning in through conceptual reconstruction: A strategy for secondary students. Inquiry in Social Studies, 10 (Spring).

Yager, R. (1991). The constructivist learning model: Towards real reform in science education. Science Teacher.

Summary for the Learning Cycle

1. Most of your students need a learning sequence different from traditional methods used to recall facts of science.

2. The worthwhile objectives (concepts, generalizations, theory, thinking skills, or dispositions) in the science topics you teach require a strategy of instruction different from traditional classroom presentation.

3. For these important ideas most of your students need a learning strategy different from traditional expository methods used for learning to recall facts.

4. Identify these important or key ideas in advance to be taught using an learning cycle strategy.

5. Use a learning cycle approach to instruction for each key idea or skill.

6. The learning cycle consists of Exploration, Invention, and Expansion (EIE). Each phase must be experienced by the student in the order described.

7. A learning cycle must be planned for a specific idea or skill. Do not mix several important concepts or generalizations in a single learning cycle.

8. Demonstrate a questioning and reflecting attitude towards the content you teach. Generate hypotheses, examine alternative explanations and encourage your students to do the same. Ask students: What do you know about....? Why do you think....? How do you explain....? What evidence do you have? Reward appropriate responses from your students.

9. Begin using the learning cycle slowely through trial lessons. This provides time for you and your students to learn to become more familiar with the changes in learning activities.

10. As a novice you will meet problems and have disappointments. Expert teacher status may be years in the making, but the goal is worth it.

_____________________________________________________________________________