Build A Cardboard Cannonball Tunnel Race

When your kids are sitting around complaining that they're bored, just grab some cardboard—lots and lots of it! Chase away boredom and create your own backyard adventure with a recycled cardboard tunnel race that's full of twists and turns.

What You'll Need

  • A flat, spacious area that's safe for running and crawling
  • Lots of large, sturdy cardboard boxes, intact or broken down flat—appliance and moving boxes are great, but nearly any shipping box will work
  • A box cutter or similarly sharp tool that can cut through cardboard
  • Several rolls of duct tape or another strong tape to attach the boxes together
  • Markers, crayons, or paints to mark and decorate the start and finish lines

Get Ready…

1. Start by heading straight to your overflowing recycling bin and grabbing every shipping and moving box you can find. Turn it into a neighborhood project by asking other families, or local businesses if they have boxes to contribute.

1. Based on the size and number of boxes you've found, figure out how large, and how long, your tunnel will be. How many twists and turns will you make? Will there be a single entrance and exit, or open places along the way? Are you planning one enormous tunnel or several smaller tunnels? Will players have to belly crawl their way through or can they crouch or stand in spots? The design is entirely up to you—but make sure your tunnel is wide enough so nobody gets stuck!

3. Sketch the tunnel on some scrap paper.

4. Double-check the size of your play space to make sure your tunnel will fit, and make note of any obstacles you'll need to workaround. At the same time, remove anything sharp or rough from the ground.

Get Set…

1. Choose a day with no rain in the forecast.

2. Sort your boxes according to size and condition. Use the biggest, sturdiest boxes to anchor your tunnel, and consider how you can cut and configure smaller boxes or sheets of cardboard to assemble the rest.

3. Bring all your materials to the backyard and assemble your tunnel on site.

4. Open the end flaps of the intact boxes and extend them so each box has two large openings, one at each end. At the corners where the flaps meet, use small pieces of duct tape to secure the end flaps to one another. This will keep them extended and add length to your tunnel.

5. Line the boxes up according to your design.

6. Begin taping the boxes together to create a tunnel that looks like the one you've drawn. Overlap the end flaps just a bit and then tape all the way around the boxes to secure them to one another. To create an angle or a hard turn, try folding in or cutting off one or more flaps when attaching the boxes with the tape. Fashion your own boxes with extra sheets of cardboard, and fill in any empty spots by taping in some scrap pieces.

7. Keep taping until your tunnel is complete, then double-check to make sure you've used enough tape to hold everything securely.

8. Mark and decorate the start and finish lines on the boxes using markers, crayons, or paints.


1. Gather the racers and show them where the tunnel starts and ends.

2. Line the racers up near the starting line, from youngest to oldest. The youngest racer goes first!

3. Yell "Go!" and start the timer for each racer. On "Go!" the first racer dives into the box and scurries through the tunnel. Stop the timer and record the time when the racer emerges from the other end.

4. Whoever makes it through the tunnel fastest is declared the winner!

5. Race again and try to meet or beat the winner's time from the last round.

When you're done racing, break down the boxes and consider recycling them into another backyard game, like a giant fort, cardboard sculpture, or giant art canvas.