Another great resource for teaching kids programming that I haven't seen mentioned in the discussion is Scratch (http://scratch.mit.edu/). My daughter (just turned 11) has been playing with it for a couple years now and it's pretty amazing the stuff she can create. The best part is that the scratch website hosts projects for free, so she can share them with friends and family. It's a great introduction to programming concepts.

As far as learning HTML/JavaScript, my daughter also liked Codecademy, and went through several tutorials there. She would get bogged down a little on syntax (Scratch is very visual), but I can't imagine an easier way to learn HTML/JavaScript.