I love teaching biological sciences because you get to teach all the fun and controversial stuff (sex, drugs, evolution, and just plain awesomeness)! Isabella Rossellini has a wonderful series that explains the sexual reproduction of animals, Green Porno. Let me just tell you, IT IS AWESOME! I am going through them now to see which ones might pass the mustard at my conservative school. It is priceless... Here is a clip on how bees mate.