For Kids

Science Experiment: Potential and Kinetic Energy - Marshmallow Catapult


Every object on earth has potential energy. That means it COULD move even if it isn't right now. When an object IS moving it has kinetic energy.

In today's demonstration you are going to store energy in a spring. That spring will have the potential to move, but it won't move until you let it move. The catapult you make is going to transfer energy from the spring to a marshmallow. The marshmallow will have potential energy until the catapult releases, then the marshmallow will have kinetic energy as it flies through the air.

You Will Need:

  • Kleenex Box & 2 pencils OR 10 popsicle or craft sticks
  • Rubber Bands
  • Milk Jug Cap

Websites that will give you good directions:

Websites, Activities & Printables:

Science in ContextScience in Context: Potential and Kinetic Energy is a database you can use in any IndyPL Library Branch or at homey. Login using your IndyPL library card number. The Science in Context database will show you articles, images and videos to help you learn about potential and kinetic energy.


You can also ask a math and science expert for homework help by calling the Ask Rose Homework Hotline. They provide FREE math and science homework help to Indiana students in grades 6-12.


Use your indyPL Library Card to check out contraption books at any of our locations, or check out e-books and e-audiobooks from home right to your device. Need help? Call or ask a Library staff member at any of our locations or text a librarian at 317 333-6877.

Stomp Rocket and Sling Shot Science - How Physics Makes Catapults Work

For kids who like to tinker and build here are projects books using things around the house to make some fun contraptions like stomp rockets, catapults and sling shots. Other books will teach them about the science behind why these clever mechanical wonders. #indyplkids IndyPL_CarrieW

The Art of the Catapult

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Instructions and drawings for building ten model catapults.

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30+ Amazing Science Projects You Can Build for Less Than $1

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Use things around the house or out of the recycle bin to design and build 30 different projects.

Break the Siege

Make your Own Catapults

Ives, Rob

Step-by-step instructions to use basic engineering and physics to build catapults and other machines.