Isis: Leave him alone. He doesn't deserve your pity, If he wants to hang out with you, tell him to stop being a douche.
Victoria: Don't be mean to him. If you need to talk to him, be civil about it. Make sure he gets the point, but also be gentle. Also, make sure that your class understands his situation, that he can't help but be a douche bag.
A lot of other girls like my crush, and it's getting frustrating because I feel like my chances with him are slimming down. What can I do to increase my chances?
Anna: Make a move. Be his friend, because that's a good foundation for any relationship. Friendship is a lot stronger than being just a "kalandian". Nothing will happen if you don't do something.
Reign: You should approach him and get to know each other. Just like Anna said, it's best to befriend him. You should also give him hints that you like him, and maybe he might reciprocate. If he doesn't, well you can't really force him to. Maybe he's just another happy crush.