Makes me glad to know the schools in my small town formed plans for active shooter situations about 5 years ago and actually practice drills every year, just like they do fire or tornado drills. Being in law enforcement and being married to a teacher, it was easy to facilitate this type of predardness in my wife's school. I would encourage anyone who knows school administrators, teachers, ministers, workplace managers, ect. to check with these type of people and see if they have some type of plan for thier facility. If they don't, questions from concerned people should get the ball rolling.
I know there are a lot of former military and law enforcement types on the forum who have probably already done this. Still, it never hurts to check.
Noah