How To Build A Tennis Ball Catapult

By keeping some basic guidelines in mind, you can learn how to build a tennis ball catapult. This project can be done as either a lesson in science, learning about the physics behind the catapult, as well as simply a fun afternoon experiment. Be sure to have a large supply of ammunition handy before shooting off the tennis ball catapult, as your friends will want to see it in action over and over!

Equipment needed to build a tennis ball catapult:

1. Use a can opener to take off the bottoms and tops of five aluminum cans of the same size. Clean the cans out well. Use the pointed end of the can opener (which can be used to punches holes) to form eight triangles around the bottom side of the last can. Make sure this can has been thoroughly cleaned and dried. On the opposite end of this same can, hammer a nail into the can 1/4 of an inch from the bottom, making a small hole.
2. Tape all of the cans together, using tape that is secure as possible. Make sure the can with the nail hole is last in line, and the nail hole should be on the outside end of the chain of cans.
3. Carefully drop the tennis ball into the can chain on the end that has not been altered with the nail. At the same time, position the lighter fuel spout in the hole created by the nail, and carefully squeeze a small amount of lighter fuel into the launcher. Slowly blow air into the opening of the tennis ball catapult, vaporizing the fuel.
4. Light one of the matches, and place it at the opening of the hole made by the nail. This will cause the tennis ball to go shooting out of the tennis ball catapult.