Contained in Warb’s paranthetical is the idea that a gun safety lesson in a school can be legitimate but this guy shouldn’t be teaching it based on actions evincing recklessness. mfm takes the view that no such class is ever acceptable and/or any accident is proof of absurdity and incompetence.
I’m not sure whether a gun safety class is acceptable or not, but it is certainly not legitimate for a teacher to decide to do this on his own without the school’s knowledge or permission.
Given the school’s reaction, I’d be surprised if this was done without the school’s knowledge or permission. You’re right there’s a lot we don’t know here.