Wow! If you like history or just like playing with timelines - check this out!
Google News Timeline
When you first pull it up, it will give you the current week. But you can also enter in any week of your choice. I kept putting in older dates to see how far back it would go. I went all the way to the 1700's.
Now it that wasn't cool enough on it's own, you can tell it to use more sources for the timeline. It defaults with Time & Wikipedia. You can add other sources such as newspapers & sports sources.
For the classroom, this would be a great way to show your kids what was going on during a certain time period when you're studying a topic in well, any subject! You'll love it!