Ask HN: My 12 year old nephew wants to make a game, how do I help him?

My 12 year old nephew has shown real interest in learning how to create computer games.

How do I help him the best, is there any drag and drop free tools or games about building games?

I am a web programme and is willing to help him, but we do not live nearby so I have to be able to help him mostly by email/skype.

Any ideas and pointers will be appriciated!

PS. English is a second language to both of us, he is ok at understanding but not too complex.