Aren't schools regulated in USA? You can't do this in the UK, it would be appealed to a higher authority and the school would be forced to back down. The head would probably be forced to resign. I was "excluded" from school more times than I can remember, and the vast majority of the time the school was forced to take me back. Excluding children from UK schools is not easy when there's no suggestion of violence or drugs, you have to basically cause a teacher to have a meltdown.