A living document being edited right now by dozens of educators. That document (embedded below) contains dozens of tips on how to use the iPad in the classroom. From the Brushes app to learning how to play music, there's a lot of surprising and useful tips.
Great Timeline Builders
Timelines are standard in the history teacher's playback. Timelines have uses in other content areas too, but I don't know history a teacher that doesn't use timelines at some point in their curriculum. The following are three good timeline building tools. Timelines built with any of these three services, X Timeline, Mnemograph, or Time Toast, can be shared and embedded into wikis and blogs.