Hstry is a nice new online too for creating timelines. Richard Byrne just wrote a post about it, and I’d suggest just you visit his blog to learn more. As he points out, one of the particularly nice features of this free tool is that teachers can create virtual classrooms for their students.
Speaking of Richard, he also has created a chart comparing the different features of several timeline sites, and that’s certainly worth a visit.
I’m adding Hstry to both The Best Tools For Making Online Timelines and to The Best Sites That Students Can Use Independently And Let Teachers Check On Progress.