Thanks Rubble, I don't use any graphics programs myself and had considered Gimp for him, but was a little concerned that it might be a little complex for him to start off with?
Thanks for all of that oddz, you make a great point about pen and paper. The child just wants to play around with a graphics program for the moment, he likes drawing and is interested in technology. It's not intended as a career choice or anything like that, just a bit of fun or a hobby really.
Thanks bluedreamer and TechnoBear, they look interesting and I will pass them on to him.
The child in question does use an iPad, so if anyone had a suggestion for a particular program to use on that, it would be great?
Thanks again everyone, I appreciate it!