When you build your own mini trebuchet from craft materials, launching projectiles becomes a source of scientific exploration! Explore physics and engineering while you learn more about this medieval tool.
In this week's family-friendly physics activity, kids bring a medieval siege tool to life when they build their own mini trebuchet. While similar in concept to a catapult—they both launch projectiles—a trebuchet differs from a catapult in the kind of energy it uses. A trebuchet has a lever arm with a large counterweight on one end and a smaller projectile on the other end. When the counterweight is raised, the trebuchet has gravitational potential energy. When the counterweight falls, the lever arm rotates, and the potential energy is converted into kinetic energy, which propels the projectile through the air.
In this week's physics activity, students build their own DIY mini trebuchet using wooden craft sticks, a straw, a pencil, and other household materials. Once assembled, kids can explore the way a trebuchet works to launch an item and can experiment to see how the movement of the lever arm relates to the path and distance of the projectile. What happens if you start with the counterweight higher or lower?
Do This Activity
The following Science Buddies activity on the Scientific American website has all the information you need to do this science activity with your students at home (or in the classroom): Build a Mini Trebuchet.
Students interested in learning more about the physics of trebuchets or catapults may enjoy the following hands-on projects and ideas:
- Bombs Away! A Ping Pong Catapult
- Under Siege! Use a Catapult to Storm Castle Walls
- Bet You Can't Hit Me! The Science of Catapult Statistics
- Launch Time: The Physics of Catapult Projectile Motion
- Into the Wild Blue Yonder: The Science of Launching an Airplane by Catapult
- Projectile Physics and Catapult Science
- Give It a Lift with a Lever
- Effect of Trebuchet Arm Length or Counterweight Mass on Projectile Distance *
- Family Fun with Physics: Launching Plastic Eggs with the Ping Pong Catapult
Make It Your Own
This kind of DIY engineering activity offers plenty of room for student creativity and exploration. Students can try different materials, different designs, and different projectiles.
Turning this kind of STEM activity into a game can be a great way to get kids engaged. Set up a goal or scoring bins and award points based on where the projectiles land. As they work to increase their scores, kids may find new and innovative ways to improve their trebuchet or catapult design!