I remember my physics teacher casually mentioned the planes crashing and then went on with his lesson.

It wasn't until after 10:00 that I learned what really was going on. All my other classes (except math with the same teacher) were focused on the day's events. We couldn't even watch it on TV in class; since the school's under construction and the cable wasn't hooked up.
And to think I still managed to have homework on that day; I couldn't even watch the news at home.