Sure there is. New rule to be a teacher: You must have served in the military or police to get a teaching certificate. You must be able to carry and use a firearm.
Schools must have multiple exits, but only one entrance, a hardened one, with two armed guards behind glass that control the doors like you would see when entering an American Embassy.
All who enter would have to pass through a metal detector beofore they are allowed inside. Easy as pie.
As a Public School inmate, I did frequently think about the analogue of school as jail (and I liked to go get some learnin’ most days).
You mean like in Libya?.....