Preceden (click to view video)
I have been working on the history of my home town, and the book I am using is organized by subject and time, making it a little difficult to keep track of events as they occurred. I just came across this great website that easily allows you to create a timeline. It can be useful for both you and your students.
This will allow you to create both events and time periods, categorizing items by color, and by creating new layers. This is a great way to organize history for your students, and it can be accessed at home as well.