Could we start with bullet-proof entry doors? Our school entry doors are all glass. I have not checked to see if a bullet would shatter it. Usually the office is right next to these doors. Anyone in the entry office is vulnerable.
With all of the camera angles from the shooting, they need someone monitoring them all at a central location. If thisshooter had been spotted while still outside, police could have been called earlier...silent alarm, maybe? And maybe s gun waiting inside when the doors were breached.