For Kids

Science Experiment: Potential and Kinetic Energy - Marshmallow Catapult

07/13/2020 | Science Experiments

Break the Siege

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.

Watch NASA astronaut Joe Acaba demonstrate kinetic and potential energy on the International Space Station by showing how an object’s potential energy changes.

Try it at Home! 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, Printables & Activities:


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