How to Make a Catapult Out of Two Pencils and a Rubber Band
- 1). Place two pencils of equal length into a solid base, such as the ground or in a hunk of foam. This will keep the pencils stable when the catapult is launched.
- 2). Break a rubber band and tie one end to each of the pencils. A simple slipknot will work. To tie this knot, loop each rubber band end around itself and pull the ends tight in the same way you tie a shoe, then fold the rubber band ends to create a loop. Pull one end through the loop and tug to tighten it.
- 3). Staple a small piece of cardboard to the center of the rubber band to use for a seating device. The cardboard should be about half the size of a matchbook cover. This is where you will place the tiny pebbles you want to launch.
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