I'd say your only hang-up would be that anything you say in public could be used against you by your employer...even if they say they wouldn't. So it would be best to not be exceptionaly down on the school system that you work in. I would also refrain from using a lot of bad language. I'm sure your contract has something in it that gives them the ablity to boot you for conduct unbecoming of an employee. But past that do what makes you happy. Life is short. Heck you might find that you're talented enough that you make it in the comedy industry and don't need the teacher job.