Weapons in schools should not be allowed. Faculty should not feel the need to take it to another level with weapons and if they do then they should call the police immediatley. There are other objects around a classroom that teachers could use as a weapon to stop someone from acting up, firearms are not necessary.
Weapons are absolutely necessary to have in every school. Since 2010, there has been 43 school shooting throughout the United States. Not all of these school ended in causalities because they had a police officer near by the school. It is impractical for a teacher to pick a classroom object, such as a ruler, to stop someone with a gun. If a police was patrolling the school, most of these conflicts would be stopped before they even happen. All teachers should have some object to go up against the shooter in case the police can not reach the room in time, like pepper spray. School is suppose to be a safe place to send your children not some place to be scared of.
So a police officer should be mandatory in every school you are saying. A police officer with a gun is understandable because they know when and when not to use it. A teacher with a gun though is much different and is a big liability to the teacher and the school. Teachers should not be allowed to carry guns on them or in their desks for any reason at all. Nothing that bad happens in a school where a teacher needs a gun and if there was a police officer in the building or on campus then there wouldn't be a reason to. Most public high schools do a have a patrol officer on campus which is enough.