Should teachers carry guns? No. That’s a foolish idea. If you doubt that, consider a school hallway during change of classes. It’s elbow-to-elbow. It would be way too easy for some nutty kid (or group of kids) to strip a teacher of his gun.
Should carefully chosen and trained teachers have access to guns? Sure. Just store those guns in safes bolted to the wall.
I don’t think arming teachers is the answer. It’s asking for trouble. A kid could strip a teacher of hit or her gun while the teacher is otherwise engaged in teaching other students. The number of school shootings could actually go up. What if a teacher decides to use a kid for target practice? Does an armed Leftist teacher even further chill freedom of speech and the exchange of ideas? I would say yes.