No Glue Catapults

No Glue Catapults
Collect
• 9 large wooden craft sticks (tongue depressor size works great!)
• 5 rubber bands
• 1 plastic spoon
• Pom-pom, cotton ball or ping pong ball
Build your catapult
1. Stack seven of the craft sticks together lengthwise and secure together by wrapping one rubber band
around each end of the stack.
2. Stack the remaining two craft sticks and secure one end with a rubber band.
3. Open the other end of the smaller stack and insert the stack of 7 sticks.
Hint: This will look like an alligator is biting the big stack and should make a T-shape.
4. Push the big stack up against the secured end of the short stack.
5. Take a rubber band and loop it around one end of the big stack. Now twist it one time and loop it
around the closed end of the short stack.
6. Twist the rubber band again one time and loop it around the other end of the big stack. Keep twisting
and looping back and forth until the rubber band is snug and the big stack is firmly attached to the small stack.
7. Use the last rubber band and secure the spoon to the top of the catapult.
Test your catapult
8. Place a small lightweight object (pom-pom, cotton ball or ping pong ball) into the bowl of the spoon.
9. Gently pull back on the spoon and let go to launch! Make sure to watch out for others!
Experiment
What happens if you try to launch a slightly heavier object? Try changing the position of the spoon by
sliding it up or down to make the launch arm longer or shorter. How does this affect your launch distance?
If you have more craft sticks, try to extend the arm even further and see what happens!
What happened?
A catapult is a lever; a simple machine composed of a plank which can pivot back and forth on a central
point called a fulcrum. A lever allows you to apply more force and makes it easier to move a load!
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