I was 18 years old and a senior in High school. I was in a public speaking class working on an exercise with a few classmates when our teacher came in and told us that a plane had hit one of the World Trade center Towers. The first thing I said was "It has happened before. A plane once hit the Empire State building during World War 2." We then went on with our day.
A few minutes later our teacher came back into the room and told us the second tower had been hit by a plane and that it was no accident. She then had our entire class go into the business room and watch the news. It was over the next 30 minutes or so that we watched as the towers fell and the reports of the other planes came in.
In a short time period the principal came in and told us to leave and not watch the news. The school clamped down on any information coming in, and I didnt really learn anything new until I got home. I must say, I was glued to the TV for days afterward, watching everything unfold.
That is where I was when it happened, and it will never leave my mind.