Next time come dressed in cammo and see what kind of reaction you get that time.
I think there should be at least one armed, trained, trusted, person in every school. Some people have no business near a gun.
My thinking on the topic goes against the flow. The school shootings I have looked at have all been fast-moving incidents. The odds of the event being initiated close enough to a school marshal or a campus security officer for him / her to intervene in time are pretty slim. One person can't be everywhere, and uniformed officers are pretty easy to locate and avoid. A lot of folks don't want plainclothes security on campuses; they are afraid that the gun-toting little gangsters might be traumatized by the presence of one of those evil guns on the person of someone not in a uniform (and remember -- always blame the gun; it's never the fault of the shooter). And a plainclothes security officer poses a whole new set of problems when the responding police see an unidentified person in plain clothes running around with a gun.Although the concept of armed teachers poses its own set of problems, I think that it has one advantage that the other ideas don't. Unfortunately, most people respond to that concept with the impression that those armed teachers are going to leave the classroom and go hunt down the threat. That would be the last thing we want. Instead, when the shooting starts the armed teacher will lock down the classroom, direct the students to cover (if any exists), and assume a position where he / she can address any threat entering the room. The "last line of defense", as it were, with the teacher defending his / her classroom and students. This will only work if several procedures are adhered to: Obviously, the teacher must be proficient with the weapon and at least basically trained in gunfighting tactics. The teacher must be physically and emotionally capable of defending the students and eliminating the threat. The teacher must give forethought to the layout of the area and have a plan; this part is critical. And finally, the teacher must be committed to carrying the weapon at all times and always concealed; there should be no instance where the teacher would remove the weapon from his / her person while classes are in session. Ideally, the students should not know that the teacher is armed. The biggest problem would be that once the novelty of being armed wears off, many teachers would be tempted to take the weapon off and put it in a drawer or a safe; this would defeat the reason for having armed educators present in the first place, and could also make the weapon accessible to unauthorized personnel. The armed teachers would need to be committed to carrying the weapon at all times.I think that a pretty low percentage of teachers would meet all of the criteria presented, but I also believe that having covertly armed teachers in the classrooms would be the best deterrent, as well as the most effective defense, against school shooters.
...until one of those armed teachers decides to go postal and becomes the shooter...