Comment Start him off with Python. (Score 1) 799
Having first started programming in the second grade (completely self-taught), I remember first starting off with BASIC. However, since that's not really around anymore and there's no real equivalent, I'd recommend python simply because it doesn't require you to initialize variables, the indented syntax is extremely intuitive, and most of the operation are easily understandable.
Start him off with simple console apps, like an adventure game, and then move into trying to imitate other apps, at which point he will almost definitely want to start pursuing more low-level languages like C.
For me, I went from BASIC directly to C and then from C to python. The transition from BASIC to C was really difficult due to the many differences but it goes to show you that no matter what you start off on, you'll do fine.