sweetie... it can be rough when dealing with a child who does not behave within the norm... and sometimes you have to take a pro-active stand on it. I myself have dealt with similar issues since my oldest was young... but she does have a medical condition. I would agree with the other comments about setting up a meeting with the school, to discuss ways the school can help your child.. like maybe counseling which did help my dd with her anger. I would also suggest going to your child's doctor and talking about these problems... he my do some tests make sure that something medically isn't going on. From there your doctor my refer you to other therapists who can help your child.
The first step is realizing you have a problem bigger then you can handle... and that is scary. But you can't change it if you don't acknowledge it. I myself had to make a huge decision at the end of my dd's 7th grade year... one that would affect her for the rest of her life, and so far this school year we are seeing a huge change in her and she seems to like school again. I believe that I made the right decision, and I'm happy to see her smile again.