Even if you armed just a few teachers and they were highly trained, that could present a different set of problems. For instance the police get a call of an active shooter at a school and deploy their SWAT team. The team enters the school and encounter a highly tense and dangerous environment. If they encounter someone holding a gun or possibly shooting it, it would be easy for one of the armed teachers to be mistaken for the active shooter and be taken out by the SWAT team and compound a tragic situation.That is exactly my thought. If you are going to arm a teacher, it needs to be a teacher who already owns AND knows how to shoot(prior military or police training, hours upon hours of range time, etc.)