I am a teacher, and here is one I always wished a kid would try...
Why do some people write with their right hands, but yet they bat left, while the next person writes AND bats right-handed? I am a hockey player, too, and I know that most of my team shoots left, but writes with their right hands. I live in Canada. In the USA, more players shoot right than left, but in Canada, more shoot left. More Canadians golf left, too. Weird.
All of these puzzle me...I am not sure where you might take it, but as someone who has judged a lot of science fairs, I'd be interested in that project.