I have been through the same thing too. The first thing i would recommend is that you do not pick your daughter up from school. That is only rewarding her. We went in when it got really bad with my son and calmed him down and then left. You do need to get an advocate. Our school sabitoged everything. My son had 3 diffent 1 on 1 aids. The first one didn't "fit" with DJ. The second one was sent from heaven. But because of budget cuts (so they say) she was bumped. The third aid was very good friends with the resource room teacher and principal. I found out later that she was doing things like taking his food away from him at lunch so he would scream. (my son has never had a problem with lunch until the third aid, lunch is his best subject. I could go on and on.
I would keep a journal of everything. If it gets to bad go to school with her. That way you can see what is going on for your self. I would hide arround corners and what not so that my son wouldn't see me.
Eventually going to school was tourchure for DJ and we pulled him out and put him in an A/I classroom where he is doing great. We have great teachers and he is learning to read and write. The fact is the school didn't want him and were doing everything borderline to leagel to get him out. Our desision was right for DJ but every situation is diffent. Just remember you know your daughter better than anyone. Schools think they know our children better than us because they have a degree. Well we parents have a degree to it's called a BIRTH CERTIFICATE. We also have constant on going training.
Good luck and if you need anything let me know.