My son's memory of 9/11. (Note he wasn't attending a public school)
"I was carpooling to second grade. We heard the news on the radio and the girl's mom who was driving was extremely shocked. Later in the day, we all sat on a mat and prayed about it in class, which I remember thinking was overblown given that NYC was a faraway place that I had never visited and had only an abstract conception of."
He's 30 now. The pool of people who have no living memory of the day keeps growing.
Not having a living memory of that day is probably better.