At one our local high schools we had same issue with a Canadian coming here to play and lied about his age. Was not nearly as outrageous as being 29 years old, I think he was actually 19 or something. But nonetheless, the school had to forfeit every game he played in once the league found out.
Never played basketball in school but I cant deny how much fun it would be to play high school football at 29 years old. Slap on my old #33 jersey and score 4 tds against Andrew Johnson High with my final game winning td coming in the final seconds while running over "Spare Tire" Dixon for the city championship.