I was eight years old and in my 3rd grade classroom when the 1957 Daly City earthquake happened. The building had folding interior walls between classrooms. This was at Brookside Elementary School in San Anselmo, California.
We heard some rumbling from the direction of the street, looked up when it continued and a student said, "Must be a really big truck." It got louder and the teacher hit the bell on her desk, "Ding! Ding! DING!" That was the signal to take cover under our desks.
We all instantly obeyed. No hesitation. I heard a soft pop! from the ceiling and those of us who could looked up to see a light fixture swaying lower than it should, with some dust drifting down.
We stayed under our desks for several minutes, until the pre-arranged All Clear signal came from the school office and the teacher told us we could get up.
I don't remember whether school was then closed for the day. I do remember my father telling us that evening that he had been on the fourth floor of his San Francisco office building during the earthquake, that it had swayed a bit, that he immediately moved to a doorway to stand under it and was about to run for the stairs when the earthquake stopped.
It was interesting to discover how immediately and totally we eight year-olds had obeyed the earthquake signal drill.
I remember it well because I have that kind of memory, and because this was the first real emergency I ever encountered.
That is a great memory.