Whan do kids start getting good at Mario Kart? I'm playing with my wife's son while babysitting as she goes out with her boyfriend and he consistently gets last place. What is so difficult about staying on the road and always holding down the A button?
I was able to get all the gold trophies in Double Dash when I was 5. So if your wife's son is around the same age and he isn't posting respectable results, he has terminal skill issue and you should return him.