Maybe each student should be issued a standard bulletproof police shield, which they'll carry on their little backs on top of their backpack - ready to deploy at the first sign of a mass shooting. It'll be like a rite of passage, when you turn 6 you get your first police shield, a great memory. It weighs about 15 lbs so they'll get swole too, we'd be fixing the childhood obesity problem at the same time. When a shooting happens they can immediately get into the testudo formation their teacher will have taught them. This'll give the teacher enough time to run and get their special issue teacher assault rifle. The teacher rifle will have psychedelic flames on each side so the sacredly-cat liberal teacher can feel less intimidated and more courageous when trying to kill the mass murderer. The teacher goes under the testudo, pokes the little barrel of the rifle out, and then dakkadakkadakkadakkadakkadakka. The shooter is dead. Then after the shooting the kids can go show their friends in the other classes the bullet indentations in their police shields, they'll get massive cool points. "Check out my shield's bullet indents, brah." "Woah, not fair, mine's only a plain-skin."