I never understood how simpletons and idiots cheat at the most mundane things....
I've seen this with Cub Scout Pinewood Derby cars as well as elementary science fairs. Our solution was to create some parent competition for the Cub event as well as 'artistic' categories for the kids. The science fair was made non-competitive to discourage the parents from participating. As it is, the kids pick cookbook projects off the internet rather than investigate something of personal interest. It's a sad reflection on our culture.