Most of NYC high schools which are in troubled areas have metal detectors at the main entrance. Students form long lines to walk through the detectors and send their backpacks through. There are still numerous doors all over the building which can and are propped open by students to let their buddies through, defeating the entire purpose of scanning. It is also possible to defeat the metal detectors by putting razor blades in one’s mouth or wrapping them in duct tape, for example. Also, students have been known to utilize broken glass (such as a broken beaker in lab) or large belt buckles, etc. as weapons. So I don’t think it’s possible to make schools super-secure. You still need multiple doors for fire safety, so that people could escape.
good points. But If you make them all go through one entrance and make all other fire escape only doors (that would trigger and alarm) that would work.