I remember that, too. I was born in 1956. We had to get under our desks during some of the drills, and sometimes we would cower in the hallways covered by blankets. Even at the tender age of 6, I remember wondering just how these crazy adults thought we were going to survive a nuclear attack this way.
Remember the air raid siren testing on Fridays at 11 am? That sound still makes my skin crawl.
Second Wednesday of every month at 11 Am for me.