Don't worry man! I had a lot of bullies in Primary that bullied me for my YouTube channel etc. I stayed strong and said "Fuck it. Why not fight fire with fire" So I went insulting them and I know I shouldn't have but it worked for me. I'm not telling you too fight but if they insult you you can A) Ignore them which will annoy them more but it will show you're strong
Go to the teacher. It'll sometimes work depending on the person C) Fight back with insults or D) Get some friends with you so you look bigger and you have backup if needed