I Dont know! (help)

There's this guy at school who has a girlfriend. But, you wont belive the stuff he does in class.
In science, (i sit across from him) he stares at me and smiles the whole time. It's soo anoying. And he rubs his foot up and down my leg.

In P.E., ( he still sits next to me) while the teacher was talking, he starts humping the friken floor saying my name and making sounds. Like, half of the class started laughing. He does this in Math and every other period i have.

Ugh! What should i do? (Beside tell the principal)