How to Build a Cardboard Marble Run

Learn how to engineer your own gravity-powered marble maze using recycled cardboard and basic household supplies. HowTo: Family Edition: family how-tos that actually help.

1. Prepare your track pieces. Ask a grown-up to help you cut your cardboard tubes in half lengthwise to create open U-shaped tracks. You can also cut some of your cardboard scraps into smaller ramps.
2. Build your base. Find a large, flat piece of cardboard to use as your wall or base. If you have a large box, you can build inside it to keep your marble from rolling away.
3. Create your gravity path. Tape your tubes and ramps onto the base at an angle. Start from the top and work your way down, making sure each piece leads into the next one.
4. Test and adjust. Drop your marble at the very top. Watch where it goes! If it falls off or gets stuck, adjust the angle of your tape or add a small cardboard wall to help it stay on track.