Simple Machines: Hands-On Projects for Kids

By James Rodriguez · October 8, 2026

The Six Simple Machines

Every complex machine in the world is built from just six basic mechanisms: lever, pulley, inclined plane, wedge, screw, and wheel-and-axle. Teaching these to children gives them a framework for understanding how the physical world works.

Build Projects

1. Cardboard Catapult (Lever)

Use a cardboard box, rubber bands, and a plastic spoon. The spoon is the lever arm, rubber bands provide force. Challenge: launch a pom-pom into a target bucket at varying distances.

2. Pulley Elevator

Thread string over a doorknob or dowel. Attach a cup as the elevator car. Kids learn that pulling down lifts the cup up — force direction changes. Add a counterweight for advanced exploration.

3. Marble Run (Inclined Plane)

Cut paper towel tubes in half and tape them to a wall at angles. A marble rolls from top to bottom through the track. Kids experiment with angles and speed.

4. Doorstop Wedge

Compare pushing a heavy box across a flat surface versus sliding a wedge underneath. Discuss how wedges split force in two directions.

Assessment Questions

After each build, ask: "What makes the work easier?" "Where is the force going?" "Can you make it do more with less effort?" These questions develop engineering thinking.