Rather belatedly... the solution to Puzzle #5 was posted a few days ago. Puzzle #6 is now also available.
Also rather belatedly, Dave Winer has an interesting take on the recent code.org promotional video. Stand out quote:
Primarily you should do it (ed: programming) because you love it, because it's fun -- because it's wonderful to create machines with your mind. Hugely empowering. Emotionally gratifying. Software is math-in-motion. It's a miracle of the mind. And if you can do it, really well, there's absolutely nothing like it.