The teacher's that my 4 year old son have are not ...

The teacher's that my 4 year old son have are not the most kid friendly people. They're always trying to find a way to exclude him in the activities of the other kids. I've tried to let it roll off my back but I think that's giving the impression to them that they can continue to treat my son unfairly. I have been quiet enough about the issues that I have with them but everyone has a breaking point. I'm looking into filing a complaint against them. The school is alright, but these 2 teachers? They should be teaching high school acting like that.