A strange thing happens when some people are packing a gun. They reach for it too quickly, when ordinarily they would react differently, use a different approach or tactic, if they didn't have one. Some teachers are no different.
Many teachers have actually attacked students and beat them. Many students have attacked teachers and principals and beaten them. If the teacher, principal, even the coach has a gun, some will use it on students. You can count on it.
Allowing teachers to have guns, actually increases the possibility of teachers shooting students.
The whole thing about teachers and armed guards in schools is ridiculous, because a killer can shoot into the play ground from a distance, or shoot students going to and leaving school. Gun manufacturers money is causing these jerks to come up with these lunatic ideas.
Teachers can and have gone off on students, now they want to give them guns? Now I know how to take care of little Johnny, pop a cap in his as$.