Unfortunately at this point the "view/edit source" button is exactly the same as on browsers... view source. It only works for web pages and it's not editable. I think the editable version is in the works.

I do think it's a great idea, but I imagine it would be very overwhelming for a kid who has never used a computer before, let alone programmed (in a foreign language, too, most likely).

What would be really neat was if in addition to opening the source, it also had some sort of dynamic tutorial that would explain what the kid was looking at. For example, they open up a webpage and it explains the HTML to them.