Thanks! I just looked at the mindstorm nxt 2.0 (is that the only product available currently, with other pieces that can be purchased to supplement it?), and I think DS might be too young for that. Although if it has the very detailed visual directions like the complex lego creator type sets do, He may be able to follow on his own, with help as needed. If the directions are minimal, we should probably wait on that and work with some intermediate building set first. Any advice on the mindstorm directions?

the Georello gears looks pretty interesting-i think he might enjoy that!