Here are even more additions to The Best Sites To Help Teach About 9/11:

Ten years later: A lasting impact on the world is an interactive from The Associated Press.

9/11 – the comic book

9/11 timeline: The story of the day is from the BBC.

9/11: Ten Years Later is from The History Channel.

9/11: The Day of the Attacks is from The Atlantic.

The Tenth Anniversary of 9/11
is a TIME slideshow.

9/11 anniversary: photographers recall day of horror – interactive slideshow is from The Guardian.