Large Groups
Classroom and homework activities illustrate how wheels and axles help with force and motion.
When things rub together, it causes heat and makes them slow down. Without wheels, your vehicle cannot move or moves very little. There's too much rubbing between it and the ground. Wheels reduce the amount of rubbing. You can move a heavy object using less force, but putting a wheel and axle under them.
1. Use a Science Process and Thinking Skills
2. Manifest Science Interests and Attitudes
3. Understand Science Concepts and Principles
4. Communicate Effectively Using Science Language and Reasoning
Invitation to Learn
Have the students rub their hands together quickly. Ask them "What did you observe happening?" Tell them that when things rub together, it causes heat and makes them slow down.
Prior to the activity
Have the students make a vehicle body at home or at school.
Activity
What's Happening?
Without wheels, your car can't move or moves very little. There's too much friction (rubbing) between it and the ground. Wheels reduce the amount of friction. You can move a heavy object, using less force, by putting a wheel and axle under it.
Curriculum Integration
Math/Science
Objective 4: Use appropriate techniques and tools to determine measurement.
1. Measure and record the distance the vehicle traveled with and without wheels.
Extension: Have the students pretend that they are the cavemen who invented the wheel. Instruct them to make a cave drawing advertisement trying to sell the advantage of their new invention to other cavemen.
Adaptation: If you teach in an area with little parental support, you may want to make the vehicle bodies in class with materials that you provide.
Homework & Family Connections
Materials
Have the students identify and illustrate six objects in their home, garage, carport, and/or shed that have wheels.
Possible Resources
Books:
How Do You Lift a Lion? by Robert E. Wells (Albert Whitman and Company)
The Way Things Work by David Macauley (Dorling Kindersley)
Simple Machines by Deborah Hodge (Ontario Science Center)
Machines -Spectacular Science Projects by Janice Van Cleave (John Wiley and Sons, Inc.)
Physics Lab in the Hardware Store by Bob Friedhoffer (Franklin Watts)
Playground Physics - Simple Machines by Bob DeWeese (Evan-Moor)
Science Experiments with Simple Machines by Sally Nanivell-Aston (Franklin Watts)
Videos:
Science Alliance #3, Machines
Laser Discs:
Windows on Science, Primary Vol. 3, Work and Machines Lessons 2-10
Have the students explain (written or orally) why the vehicle with wheels travels farther than the vehicle without wheels.