It depends on his age. Yes, the school has the right to suspend
   him - it is school polity. HOWEVER, I think it would be
   beneficial to bring him back in and use it to discuss civil
   liberties in social studies classes and use it as a way to teach
   civil disobedience. I'm sure it will be used as an example case
   in other high schools and colleges if the story goes nationwide.
   The danger of course: Will this encourage further civil
   disobedience and is the school prepared for it? Is it possible
   to put the genie back in the bottle? "