My best friend stole my money?!?!?!?!?

Sorry to hear that, but if you dont learn from that experience, never to trust him again, and for sure dont have anything to do with him again. If it were me, I would find a teacher that you trust and talk to him/her about this, because I think people that do this sort of thing will do it again, so when you talk to the teacher, tell them you are not accusing anyone, but just want them to know about it and to be aware of your feelings about this particular person, so that they may keep their eye on him in the future, because if it is him, he will do it again to someone else and you being a victim maybe able to help catch him in the act and that will prove to you that it was him that took yours. Good luck