The catapult is an ancient weapon used by early civilizations and usually constructed from huge logs. These catapults were usually very large and capable of flinging very heavy stones hundreds of feet in the air. If you are not looking to make a huge weapon of mass destruction, you can make miniature catapults out of household items. These catapults are designed for simple mischief and can be constructed quickly and easily.
Disassemble the retractable pen. Most of these types of pens have a bottom or top that can be twisted off so that the parts can be removed. You want only the spring and the plastic ink reservoir for this catapult. It is best to use an empty or broken pen as well (why destroy a good pen?).
Glue the spring to the upper end of the pen. The spring should be glued perpendicular to the pen (so that the spring is vertical and the pen is horizontal).
Glue a wooden craft stick to the top of the spring. One end of the stick should be directly on top of the spring and the other end should be on or close to the tip of the pen. Tape the end of the stick that is not attached to the spring to the pen. You should now be able to push down on the stick and it should pop back up immediately.
Glue the plastic bottle cap to the end of the stick that is attached to the spring. Glue the empty ink reservoir horizontally across the wooden stick. Now, you can load the bottle cap with a small object, push down on the ink reservoir and launch the object.
Plastic Spoon Catapult
Place two wooden craft sticks 4 inches apart on a work surface. The sticks should be aligned vertically and parallel to each other. Glue a third stick across the first two connecting the centers of those two sticks. This is the catapult base.
Glue one stick to both the left and right sides of the base. Glue the sticks on their sides so that it stands up. Glue two more sticks, one to each side, onto the figure. These sticks should stand up vertically. Glue a third set of two sticks, one to each side, in the same manner as first two sticks.
Glue two more sticks to the two sticks that are standing vertically. Glue the sticks flat across the two vertical sticks, one on both sides.
Tape the narrow end of the plastic spoon to the middle of the catapult base. The spoon should be able to freely move up and down while still being firmly attached.
Cut two large rubber bands open. Tie one end of each rubber band to the two horizontal sticks at the top of the catapult. Tie the other ends of the rubber band to the spoon. Now, you can bend the spoon back and launch an object.
Lay two craft sticks 4 inches apart on a surface in the same manner as the sticks from the Plastic Spoon Catapult. Glue one stick across the first two connecting all three sticks. Glue two more sticks on top of the third, one on each end, each aligned with the stick on its side. Repeat this procedure once more ending with two sticks.
Glue a craft stick vertically to the clothespin or binder clip. Glue it to the very end of the clothespin, so that about 3 inches of the stick hangs off the end. Glue the aerosol can top to the end of the craft stick.
Glue the component from the previous step to the catapult base. You should now be able to push down on the stick and launch a projectile with the clothespin.