there actually was a scintilla of sense in that; it was
the same as old school tornado drills (where you’d have
about 30 seconds warning) it might protect from some
trauma (falling lights, windows)
However the nuke drill was mostly to demoralize
I always figured it had a lot to do with maintaining control.
They didn't want 40 pumped up, half scared juvenilles running amok out of each classroom and into the halls.