The Pinewood Derby is a traditional crafting event among Cub Scouts in the United States. Boys are given a block of wood and some plastic wheels. Their job is to carve and paint the block into a car that, when released at the top of a long ramp, will beat the other similarly made cars to the finish line. When I was a Cub Scout, my Dad showed me how to add weights to the body. Doing so was completely within the rules. Adding CO2 canisters to the car, however, probably isn't. It's actually a fairly sophisticated modification because the tubes have to open at the right time. A video at the link shows how it's done.
Link via Hack A Day via MArooned | Photo: The Hell Ya Better
PROOFREAD!!!
We also had C02 drag races in scouts. In that event, obviously, co2 canisters were allowed in the cars.
Bragging: MINE WON TOO!
@Hiller: The Pinewood cars could weigh no more than 5 ounces. The winning cars always used a combination of clean aerodynamics and smooth-running wheels to win. Running straight also helped, because having the wheels bump against the track edges slows the car considerably. Those were some fun projects!