Hello Python!

It might help to have a bit more background on your nephew and his interests. If he's generally geeky, then Learn Python the Hard Way is excellent - but you need to already be very motivated to sit down and work through the exercises. Similarly, Hello World! is a good book for the complete beginner, but a 17 year old might find it a bit easy. And based on the reviewers who've looked at it so far, Hello Python! tends to do well with relative beginners, but complete novices find it a bit hard, and it annoys the hell out of some experienced programmers - not sure why, I think it's because I don't explain everything in detail and gloss over to the interesting bits :) Have you considered something along the lines of an Arduino + book? Some people seem to get a kick out of making things actually happen, rather than just appear on a screen...

I'm just putting the finishing touches on Hello Python (http://manning.com/briggs). It's not out in print yet, so I don't know whether it's what you're looking for, but you can get it on Manning's MEAP program. The basic theme of the book is that I replicate the path that most programmers follow when they learn how to program - start with something small and build up. I cover games and a couple of Python's more important tools, like Twisted, Pyglet and Django.