6 year old on seroquel | ADHD Information

Well, here we are again. From ritalin la to stratera to risperdal now to seroquel. I am at my wits end. The risperdal has helped my son somewhat. I'd say 60%. However, he just got his walking papers from his new daycare. They said they didn't have the resourses for a child like Alex. At the end of the day he didnt want to clean up so, he started jumping off tables, spitting and hitting at his teacher, banging his head on the floor. I have already had to take FMLA at work so, I can be excused to go get him or go calm him down from situations. He is now back at home staying with my mom (who is on short term disability) and his great grandmother who at 78 years old does not need to put up with this. He is a loving outgoing boy until something sets him off. "you need to clean up your toys" or "you can't go outside" anything that he does not agree with will set him off. I am almost to the point where I am thinking of quitting my job to stay home with him. If anyone has any information, any pointers, any suggestions, please help. I am at the end of my rope and don't know how much more either one of us can take. Any support groups? I am in North Carolina.