Pencil Catapult
Objective: Use pencils and rubber bands to create a working catapult.
This is a fun activity which we have completed in class. The catapults are powerful and have launched LEGO figures across my classroom and into the light fixtures. It might be best to experiment outside.
The #2 pencil is a classic school supply, and we turned a box of our pencils into a pencil catapult. The perfect back-to-school fall STEM activity! Who doesn’t love a catapult? There are so many great learning opportunities that a catapult can bring to the table from engineering design to math to science and of course fun! What you launch is up to you!
DESIGN YOUR OWN PENCIL CATAPULT
Before you sharpen those pencils, design your own pencil catapult. We have made catapults from marshmallows, popsicle sticks, LEGO, and plastic spoons/cardboard tube rolls but never from pencils! You may need and extra hand to help when it comes to holding the pencils and twisting the rubber bands. However, there are tons of ways you can build one that’s unique to you.
SUPPLIES:
Rubber Bands
Number 2 Pencils
SET UP:
Below you will see some photographs outlining the order in which we put the pencil catapult together.
STEP 1: First Picture Below, Build the Main Unit
First, you want to attach two pencils to the middle of one pencil as show below {perpendicular}. This will act as the lever arm/launcher.
Second, you want to attach that single pencil {with the two attached pencils} about a 1/3 of the way down two pencils {that are parallel to each other} for the frame. Check below.
Third, slip a rubber band onto the frame as shown below. Remember this is the tension that will affect the launch!
Fourth, add a pencil to the bottom and to the top to complete the square shape. Note that the top pencil is resting on top of the two pencils in the center
STEP 2: Build a Base
Your pencil catapult needs a sturdy base! Once you have the main frame built, you need to make a base for it. Next, we added three pencils around the bottom connecting to the main unit and creating a square on the bottom. Check out the photo below.
STEP 3: Add the Sides
Finally, you need to add one pencil diagonally to each side, creating a triangle shape on each side. This will keep your pencil catapult upright and ready to launch.
Your pencil catapult is complete! What will you launch?
Different materials will launch farther than others. Why is that? Set up an experiment and find out.
Since we are using school supplies, we decided on eraser pencil toppers to launch! Quite fun actually. In addition to simple fun, our catapult dabbles in physics and mathematics too. How does a lever arm work? Is there both potential and kinetic energy? Whether you use our design or invent your own, this STEM projects is the perfect boredom buster. Above all, have fun!
