Build a car that is powered by strain energy of a rubber band.

Note:  The gear in the back is used only as a catch for the rubber band to help it start wrapping around the axle.
The bushing on the axle at the very front is to loop the rubber band around.

How does the length or width of rubber band change how far the car can travel?

Why does having the rubber band come loose when it unwinds help the car continue to travel?

What is inertia?

How far did your car travel?

Linda Hamilton
LEGO Links of Linda Hamilton
Some Rubber Band Car Links 
ATI Transportation k12 LEGO Projects
April 7, 2001

Teacher notes:
Age level: 2nd to 8th grade
Materials:  LEGO Dacta Motorized Simple  Machines Sets or eLAB sets. Paper, pencil.  Colored pencils or crayon optional.

Procedure:  Two students work together per set.
One student should be in charge of making sure the building is done carefully and pieces are placed back at the end.
One student should be in charge of making sure the report is done well and turned in.
Math concepts:  Measuring in inches and centimeters.
Science concepts: Strain energy
Some pictures