And as for students, shouldnt teachers be responsible for whom they teach?
Yes, Chen Zen, I agree completely and wasn't arguing against that.
I was talking about what IS, not what SHOULD BE. Actual conditions need some oversight, especially when they differ from public image. As you say in your later post, "It's amazing that a teacher who teaches history or ABC's has to have a license and background check and yet another person can call themselves teacher and teach someone how to choke another person or how to use a knife or sword with no more than a empty room and a "Martial Arts" sign."