Help. Advise needed about my 14yo son?

I think you should go straight to the source. Your son is the problem not the school. Not saying he's a problem, but he's the one bullying the school just has to do what they have to do. You should talk to him about it. Sit him down as his mother and ask him why he does what he does. That it is mean and that is not how he was raised and you can't believe his behavior. If you don't discipline him he'll keep going on until he get's expelled. No one wants that. So tell him if he wants to continue going to that school then he needs to straighten up. That you guys didn't come here for him to misbehave that way. Good Luck I hope everything works out ok. :)