How to Make a Working Pulley System with Your Kids

Learn to build a simple, functional pulley system at home using everyday materials for hands-on science learning.

  1. Gather Your Materials. You'll need a spool or empty thread reel (or you can make one from cardboard), strong string or thin rope, a pencil or dowel rod, tape, and something to hang your pulley from like a sturdy tree branch or ceiling hook. For the load, gather small items like toy cars, blocks, or a small bucket. If you don't have a spool, cut two circles from cardboard and tape them to either side of a toilet paper tube to create your wheel.
  2. Create Your Pulley Wheel. Thread the pencil or dowel through the center hole of your spool - this becomes your axle. If the hole is too big, wrap tape around the pencil until it fits snugly. Make sure the spool can still spin freely around the pencil. Secure the pencil with tape on both sides so it won't slip out. Test that your wheel spins smoothly by giving it a gentle turn.
  3. Set Up Your Pulley System. Find a sturdy mounting point like a tree branch, ceiling hook, or even a tall chair back. Tie one end of your string securely to your mounting point, then thread the other end over your pulley wheel. The pulley should hang freely and be able to move up and down slightly. Make sure you have enough string length to reach the ground with extra to spare for tying on loads.
  4. Test and Use Your Pulley. Tie a small object to the free end of your string - start light with something like a toy car or small block. Pull down on the other side of the string to lift your object. You've created a simple fixed pulley that changes the direction of force, making it easier to lift things up by pulling down. Try different weights to see how much your pulley can handle, and experiment with adding multiple pulleys for a compound system.
  5. Explore and Experiment. Once your basic pulley works, try variations like creating a movable pulley system by attaching the pulley wheel directly to your load, or build multiple pulleys for greater mechanical advantage. Time how fast you can lift objects, compare lifting with and without the pulley, and let kids predict what will happen with different loads. This hands-on experimentation helps cement the learning.