Well, I mean it's an unaccredited school, and the lessons they're teaching led someone to almost destroy the world.
Sure Cozy's probably a nutjob inherently, but shouldn't they shelve those lessons, until they know more about what they're dealing with? The lessons might sound innocent and harmless, but if no one knows why they basically created an evil dictator, is it ethical to continue to teach them?
Heck, they have a "reformed" evil dictator working at the school! Who's to say Starlight wasn't grooming Cozy Glow just as much as Tirek was?