UHU, for his second plane, you could get him a Multiplex Twinstar. Dual speed 400's and a high wing design. These fly nice plus, it will teach him how to use ailerons. Or, get him a Sky Scooter Plus. Another pretty good aileron trainer. After he is accomplished with that, then I'd get a wing. My first wing was a zagi and it met its demise very quickly. Very sensitive to
CG plus I had too much ego!!!!! I fly glow and brushless wings/sport/sailplanes now but I learned on a T-52 and a Sky Scooter before I moved on.

Dave...