I read this book many years ago when my son was small and not in school yet:
http://www.amazon.com/Little-Boy-Book-Guide-First/dp/0345344669
There was an entire chapter dealing with the fact that school is more geared towards girls. In general, the "sit at a desk, listen to teacher, read a book, take a test" way of learning is not best for boys.
However, teaching children is not a task that men have traditionally wanted. Teachers are amongst the lowest paid professions. Perhaps there isn't enough money in it for men?