Uniformed guards not the answer
As a young man back in the 1960s or 1970s I would visit a coin shop in Elmhurst. The owner always had a small two shot derringer in a holster strapped to his belt.
Once I asked him if he ever had to use it. He said "not yet". Then he added, "It's so light I almost forget it's on my hip. At least I have two shots."
Now I wonder what would have happened if just one of those brave women who charged the shooter in that Sandy Hook school would have been armed with something as small as that two shot derringer.
We need to think about the concealed carry option for regular school employees. At least one per school.
With modern technology we now have small powerful pistols that weigh less than a pound, not much bigger than a pack of cigarettes.
Most of these guns hold five or six rounds. Uniformed guards are not the answer as they are too easily identified by the bad guys.