Making a rubber band car is fun for experiments and learning about potential and kinetic energy. It’s fun and easy to build a rubber band car. It’s a great opportunity to try some engineering design. Safety note: Be sure to explain safety precautions to children. These experiments use rubber bands under tension and sharp skewers. Eye protection should be used. Disclaimer: All information provided on this site is for entertainment and education purposes only. Using any information from thecasabouquet.com is at your own risk.
The basic setup is a lightweight body for the car, wheels, axles, and a rubber band to provide energy for motion. Some designs use cardboard for wheels, some use CDs. These rubber band car designs encourage children to ask questions about transfer of energy, observe, analyze, and share their findings.
- PBS Kids Design Squad Build Rubber Band Car
- Inspiration Laboratories Make a Vehicle
- Frugal Fun for Boys & Girls Two Ways to Build a Rubber Band Lego Car
- Your Modern Dad DIY Rubber Band Racer
- Education.com How to Make a Rubber Band Car
- Crafts by Amanda How to Make a Rubber Band Car
You will need to make a catch to hold the rubber band on the rear axle. You will need putty or clay to make sure the wheels are firmly attached to the axles, not spinning. Your car needs to be designed so that you have a way to wind up the rubber band and it can freely unwind when you let the car go.
When trying the rubber band car activity, I always encourage children to make it into an experiment. There are several areas where variables can be changed. Wheels: Try cutting cardboard circles or use CDs. What other objects could be used for wheels?
Car body: Use corrugated cardboard (the channels are a good size for skewer axles.) Try an empty water bottle or a small cereal box. What other objects would make a good body? Is it better to have a light body or a heavy body?
Axles: You can use skewers or pencils. Would straws work? What other objects could be used for the axles?
Rubber band: Rubber bands come in different lengths and different thicknesses. Is it better to use a large heavy rubber band or connect little rubber bands together (such as Rainbow Loom bands)?
What is the science?
Content: potential energy, kinetic energy, transfer of energy, rolling, friction, forces
The rubber band has potential energy when stretched or wound around an axle. When the rubber band is let go, it returns to its original size, releasing energy. You can see the energy in the spinning of the axle and wheels. Kinetic energy is the energy of motion. In order to move, the car has to have friction with the floor. If the car had no wheels, all of the body would be on the floor which would have a lot of friction. With wheels, there should be friction where the wheels touch the floor.
Resource links for rubber band car
- General Lab Safety resources from Flinn Scientific. Be sure to check out the Student Safety Contract.
- Potential and Kinetic Energy from Utah Science Curriculum
- Forms of energy from Energy Kids
- Wheels from Explain That Stuff
Let’s talk story
My friend Jen and I found that middle school and other age children are very interested in cars. There is so much STEM in how cars work. This is the first in a series of science ideas for a car theme. Some car inspiration: Cars 1, 2, and 3; Fast and Furious; Smokey and the Bandit; Speed Racer, Talladega Nights; Days of Thunder; Speedway.
I’ll be looking for comments below, or contact me at lisa [at] thecasabouquet[dot]com.
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What are your thoughts?