Our one story school building had apparently only one really solid wall, located in the auditorium, so the teachers would march us all thru the halls to huddle together there for the duration of the drill.

That practice would of course also been for a tornado event. Violent storms were not uncommon in Northern Ohio.

As a kid, I was only vaguely aware of the horror of a potential total nuclear war, but I strongly remember really liking being crammed tightly next to Christine Duncan during those drills. Her slightly worried smiles definitely helped pass the long minutes till the "all clear" sounded.