Dipity is a simple to use timeline tool for both you and your students to use to organise the sequence of events or dates of any topic you are working with. http://www.dipity.com/
You get 3 for free and of course you could upgrade. Some ideas include a history timeline or the sequence of events in a novel eg http://www.dipity.com/dicksonk/British-Invasions-Timeline/
The tool allow you to choose who can see it and who can contribute, making it a great collaboration tool to get a shared understanding of any topic. Once created they can be embedded into your blog.