This is cool - playing on a friend's Kindle last week, I found an app called "BASIC!" It's good old BASIC as we all know and love it, but with hooks for most of the good Android hardware like GPS, WiFi, camera, etc. It's pretty darn cool; doesn't teach you anything about Android per se, but if you want a simple/fast way to start interacting with Android hardware, it's about the quickest route I can imagine. For example:
will load your current latitude into i.
tts.speak "Hello there"
will invoke the speech synthesis subsystem and speak your text. Seems like a quick way to try out some HW-related ideas and see if they're worth pursuing; or to simply entice people that Android is cool :)