NRA has already proposed a plan, PUT ARMED PEOPLE IN SCHOOLS. but they stupidly propose to PAY them. There's millions of schools, and they are open more than 40 hours a week. you won't get any guards worth a hoot for less than $15 an hour, and that means $22 an hour for 1000 hours a year. So 50k a year, times how many schools, ? am illion? so 50 BILLION $ a year, increase in taxes.
MUCH smarter to just allow 2-3 of the teachers at each school to ccw, and insist upon and pay for their training, gun and gear, and their practice ammo. Do NOT pay them for being present, they are already THERE, and it's their ROLE to protect and guide the kids. THAT is feasible, the paid guard thing is not.