Things You'll Need
Instructions
Cut off all four tabs on the top of the cereal box.
Make a cut along one of the creases from the top of the cereal box about half the length down. Repeat for the other three creases.
Turn the cereal box upside down on top of your piece of cardboard. Push the four loose sides down to make a pyramid shape. This is the foundation of your 4-sided ramp. You can alter the steepness your ramps by cutting further along each crease and lowering the cereal box when you turn it over.
If you would rather make a "spine" (two quarter-pipe ramps back to back), cut away the narrower sides of the cereal box, leaving just the two larger ramps facing in opposite directions.
Place the ramp on a cardboard base and tape the lower transition of each ramp to it. Cut away any excess cardboard from your base.
Decorate your ramp using spray paint, stickers or graffiti art.