I left my last school after attempting suicide several times, but that was because it was a pack. By pack, I mean the 120/125 that hated me. I still don't know what I did, as I mostly kept to myself. Maybe because the RS teacher told everyone I am Jewish, or maybe some other thing. They did make fun of me liking anime, which is pretty fucking stupid as many anime series/films are absolutely brilliant. Also, because I wasn't a raging homophobe (growing up with a gay cousin and all), they always called me gay when I didn't mock homosexuality. Anyway, I moved away. It may not be perfect (Hell, it might be, I mean it was for me), but it works.
Also, violence is the other option. IF you really don't care, go to the limit. Do something to earn yourself a bit of a rep as a nutter (I.E repeatedly kicking in the balls), and they'll leave you alone. In another school of mine, I was bullied, and one one occasion, chased up a tree. I then lashed out with my foot wildly, breaking the asshat's nose. Strangely, he left me alone after that.
Whatever. Anyway, telling the teacher won't work. Adults' hands are tied, and the kid will just get pissed with you, and hurt you more. Make them respect you, or just ignore the fuck outta them. Maybe hang around with big people. That also helps.