The problem is that only the Board of Trustees can expel students. There is a 'process' that must have occured before this can happen. Should the school be in breach of this 'process' then the responsibility will fall on the principle as it is his role to see that the due process has taken place before the student and the offence is placed before the board. The school also has to find a place for the student and this is not always easy.
The day will come when a parent of a well behaved student will commence proceedings against a school. The two issues that come to mind is exam failure where the school will be held accountable for not providing adequote education due to too many disruptive students. The second one will be not providing a safe environment for the student who had been subjected to bullying. This may be physical or text bullying.
Skyryder
Bookmarks