Of course it would work, but the Left would be against it just for that reason. Their main goal is gun grabbing, not school safety.
Metal detectors don’t detect all guns or knives. Plus anyone determined to pull off a shooting can just as easy do it outside as a crowd gathers at the entrance or as students leave the campus.
Also one guard may become busy or distracted. He may also be the first target if someone comes in with a gun, since the guard must respond in time to protect himself. Unfortunately, there does not appear to be a fail-proof system. This is similar to protecting airliners. While you may prevent someone from boarding the plane, they have already entered the terminal before the TSA checkpoint.
Of course it is. As evidenced by the fact that we protect politicians with guns, we protect celebrities with guns, we protect our banks with guns and on and on.
Why wouldn't we protect our children and teachers with guns? Because the government funded schools have the power to refuse to do that. It doesn't fit their agenda and because it would work.
You nailed it I ran this on a lefty site and most admit it would work, but wanted to take people's guns anayway, The usual cry was basically "yeah it would probably work, but what do you need a gun for?"