I found this site back in high school:
http://www.bbc.co.uk/science/humanbody/sex/I thought I'd bring it up since gender has been heavily discussed the past few days. It's an interesting test and defines gender in terms of brain functionality.
It also reveals why women might struggle with math. Math is often taught in a geometric way, but women don't generally excel at geometric tasks (but they excel in other tasks!). Hence, I believe women are merely taught math the wrong way ... but that's a different discussion altogether!
I scored 100% Male in High School, but now I score 50% Male ... I think it's ideal to be in the middle somewhere since both male and female have advantages.