we have all been trained by watching countless movies of bank robberies ect to just lay on the ground and everything will be fine.
The only moment anyone had to act was immediately, which might have prompted accusations that they caused the shooter to go crazy and shoot people.
This was a no win situation.
I agree. This takes training and a mental attitude that comes with practice. For some, Situational Awareness comes (more or less) naturally, but anyone can learn to recognize potential threats and then imagine (or mentally "rehearse") options, actions, and impacts and as a result be better prepared to react quickly and decisively when necessary.
The sheep dogs are the one who protect the sheep from the wolf. LEARN to be a very good sheep dog.
Forty years of hijackings taught everyone to remain seated and take a side trip to Cuba. 9-11 changed all that and hijackers have had very poor luck since because they get mobbed. It's time to rethink getting on the floor in the first place.
Oh how good would it have felt to plant a shoulder in his ribs and drive him halfway through the front wall? At classroom distances nothing but a brain or spine hit would overcome inertia once someone started his way quickly.