I was in fifth grade, just turned ten. I remember the principal coming to the door of my classroom, with a very pale face. She must have told my teacher. The teacher told us and everyone gasped. Then we were dismissed about 2 hours early. They were afraid the middle school kids would tell us, when we were walking home, since they got out earlier. I remember sleeping over my friend's house that night, as always, on Fridays and being glued to the TV.
The earliest "event" I remember is the first manned space flight, with Alan Shepard. I was in first grade, maybe second? We had a big clunky TV in the room and got to watch the whole 30 second thing.