Being Bullied/Hit by Black Belt Korean Clmate?

I'm a sopre in high school who is very friendly towards others and have never gotten into a fight before or even close. However a new student transferred last year from a local town after moving here from Korea. He acts like he wants to be my friend (I do not want to be his friend AT ALL, I do not want any responses saying he'll stop once you befriend him because that's out of the question), but also picks on me. He has two black belts in tae-kwon-do and has continually punched me in the leg (we're in band together), one time threw me to the ground (he caught me before I hit the ground though), and just today put me in a sleeper hold for a few seconds. He does this because I tell him I'm not afraid of him and this gets him mad like today he told me that he could put someone in the sleeper hold and knock them out but I said I don't care if you do so he did after school. He gets mad when people do not obey what he says (if you don't pick up his music or something like that he gets really mad and says "you want to die?"). The problem with dealing with this is 1. I don't want to be "tattle-tale" and just go rat him out because I've done this in the past and bringing it to the administration seems to make it blow up, and 2. my band teacher doesn't take my claims seriously enough to do anything because I'm very happy-go-lucky and joke around a lot so it's complicated. I've decided by myself that next time he does something I'm going to fight back (I have no fighting experience) because I'm not his b**** and am not putting up with this anymore. Diplomacy is out the window with this guy I've told him to stop before and he doesn't and I definitely do not want to be his friend-everyone who has had a cl with him knows he's a jerk. Any advice is much appreciated (especially real-life examples and your experiences)!