Procedure:

A. Tell the students that you are going to give them a thought problem. Have them discuss and write their answer on a sheet of paper. "You are riding in a car traveling down the interstate highway. The driver takes his foot off of the gas but doesn’t put his foot on the brake. The car comes to a stop on the side of the road. Why does the car stop?"

B. Place the students in groups of four and assign roles: materials manager, two timers/recorders, and one helper. All students will also serve as shakers.

C. Describe materials and instructions needed for student groups to carry out the activity of shaking jars containing sand at different rates and times. Discuss safety precautions relating to glass jars and thermometers.

D. Key question: What happens to the material inside a jar when you shake it? Draw and describe a jar one-half full of sand after it has been shaken for five minutes.

E. Provide each group of students with two baby food jars half-full of sand, newspaper, and a thermometer. Tell the students to wrap each jar with a piece of paper towel folded over several times to form a strip about two inches in width. This will provide insulation to keep the jars from being warmed by hands..

F. Ask the students to measure and record the temperature of the sand in each jar. Have the students examine the contents of the jar. Ask the students to infer what will happen to the contents of the jars if they are shaken for a long time. Have the students record their inferences.

G. Next, ask the students to close each jar tightly and to shake each jar for six minutes. One jar should be shaken rapidly. The other jar should be shaken moderately. The students in the group can take turns during the shaking process. Each student should shake the jar for one minute at a time.

H. After shaking, the students should immediately put thermometers into the jars. After sixty seconds, they read the thermometers. While waiting, the students the students can examine the the contents of the jar.

I. Ask the groups to report their results to the whole class. Help them communicate the results of their activities using tables and/or bar graphs to justify their conclusions.

Evaluation: Collect the students’ responses to the thought problem in "A" above. Evaluate them considering the type and extent of knowledge expressed. Evaluate group skills by assessing whether all participated equally in the activity.

Procedure:

A. Place the students in groups of four and assign roles: materials manager, readers/observers (two students), and recorder.

B. Have them discuss the key question from the Exploration in their groups. During the discussion introduce the alternative conception that the energy of motion from the hand caused the sand particles to move. The motion of the sand particles bumping against each other is called friction. The friction of the sand, stopping the motion of the sand, created heat.

C. Ask each group to perform the following activities at learning stations. Instructions for each station will be given on a laboratory guide available at the station.

D. Lead a whole group discussion concerning motion, friction, and its effects. Student participation should include evidence from the learning stations and other experiences they have had with friction. The discussion should lead students to draw the conclusions that some of the energy of motion is transformed into heat energy in the objects involved and the greater the amount of friction, the more heat energy is transformed from the energy of motion.

E. As a closure, state that the greater the energy of motion the greater the heat energy produced. The rise in temperature of the thermometer indicates that a transfer of energy took place. The motion energy provided to the grains of sand or wood in the station activities was transformed as a result of friction, into increased heat energy in each grain of sand and in the wood.

Evaluation: Ask each member of the groups to write out a summary of the actions undertaken by group members at one of the stations. Each member should address a different station.

A. Provide each group of four students with problems written on three inch by five inch cards. Ask each group to perform the problem situation if possible. Whether or not they can act out the situation, they are to think about the problem and describe the chain of events by which the energy of motion in the problem becomes transformed into heat energy possessed by the objects involved. Write the key questions on the board. For each situation draw and describe "What is moving?" "What becomes warm?" and "How did the energy of motion become heat energy in the object?"

Problem 1: Your group must pump a bicycle tire for three minutes. After three minutes, feel the pump and the bicycle tire. Discuss the answers to the key questions.

Discuss the answer to the key questions. You may use the toy car to act out the problem.

Problem 3:

Problem 4:

D. Summarize the lesson by stating that when we started the activities, the students may not have been able to tell the difference between the words motion energy and heat energy, and the part played by friction in the transforming one to the other. The activities with sand in jars, stations, and problems should help them in applying these ideas successfully in your everyday lives. By observing events where something in motion is being heated, they should be able to identify the "source of friction" and apply the terms "motion energy" and "heat energy." Whether they are talking about bicycles or in-line-skates they should be able to use the idea of heat energy being transformed from motion energy.

Evaluation: Ask the students to respond to the following situations. First,