Pine wood derby
See the link below....I know....it's a ferd web site but this link will (should?) take you to a guy that actually wrote a book on building Pine Wood Derby cars. Don't let it scare you off, because these are way over the top of anything you are likely to run into. The ffcobra web site in their OFF TOPIC forum is actually trying to stage a grown-up race. You must be a heck of a guy that a youngin' searched you out for such an important mission...KUDOS
http://www.ffcobra.com/forums/showthread.php?t=95527