Unfortunately the principal sets the tone for school and it sounds as if yours isn't much good. Going above him will sadly just get him offside and get you labelled as a problem parent (it shouldn't but it will) It sounds like the counsellor is doing the right thing and trust me there are some hopeless school counsellors out there. I'm glad she has got one friend but the physical violence must stop- those kids responsible should be in very serious trouble each time this happens. I am pleased to see that one was suspended but since the school was aware it was this serious they should be monitoring the situation closely. I am going to do soem research at school into who you could contact for help within the dept. and get back to you but it may not be until next week.
Your little girl is lucky she has caring parents.