RobinTKD
Blue Belt
I've often used Tongue Soo Do in fights 
But seriously, TKD? Well kinda-ish, I did a nice jump axe kick on a guy who started pushing me around outside a Tesco store once, but it was only 1 technique and he wasn't getting up any time soon, but looking back, if he'd done it to me today or yesterday, I would have just walked away from it.
What country do you live? If its the USA, then I can't help you in terms of how your school would handle it if you told them what was going on. On the other hand, if it was the UK, then expulsion rarely happens over here, including for repeated bullying, it'd probably take the involvement of a weapon to get expelled in most schools here. I'd still tell your teacher though, and if the worry is that they'll get you after school, and it's a gang of people against you alone, if you can't get away, then fight like hell, use every technique you can cause if it was me, I'd fear for my life and I wouldn't hold back.

But seriously, TKD? Well kinda-ish, I did a nice jump axe kick on a guy who started pushing me around outside a Tesco store once, but it was only 1 technique and he wasn't getting up any time soon, but looking back, if he'd done it to me today or yesterday, I would have just walked away from it.
What country do you live? If its the USA, then I can't help you in terms of how your school would handle it if you told them what was going on. On the other hand, if it was the UK, then expulsion rarely happens over here, including for repeated bullying, it'd probably take the involvement of a weapon to get expelled in most schools here. I'd still tell your teacher though, and if the worry is that they'll get you after school, and it's a gang of people against you alone, if you can't get away, then fight like hell, use every technique you can cause if it was me, I'd fear for my life and I wouldn't hold back.