Regarding Codeacademy: Fairly well all ages. I like it, DS7 likes it. I probably know a few dozen programming languages and DS had only previously messed around with Scratch and some programmable toy robots. Probably my main complaint is it is more concerned about imparting the language elements over nailing down the concept of programming.
For a complete novice, I'd suggest something like Scratch first (
http://scratch.mit.edu/ ) as it gets into the concept of programming without getting too concerned over syntax. But if your sons are going to work together on learning Python that probably trumps anything else.
