As a game designer, i'd say Physics, algebra, geometry come in VERY handy. Now, i am not familiar with how these topics are taught in the US system, but assumin

As a game designer, i'd say Physics, algebra, geometry come in VERY handy. Now, i am not familiar with how these topics are taught in the US system, but assuming your options are a progression, i'd say pre-calculus should do it. Similar to your son, I have been programming since an yearly age. We had Macromedia Flash back then, and over the course of my academic life, as i progressed in the Mathematics courses, my programming capabilities increased with leaps and bounds. For example, the movement in my games was usually similar to Pacman or bomberman. No arcs, or curved paths existed. As i learned about 2D motion, i started making Platformers. As i learned trigonometry, I started making games involving curved paths on a 2d plane. Even a realistic Car game. i remember coming home from high school the day they taught us about "Radians" and began usign the sin, cos, tan funtions of ActionScript (because the documentation said it used Radians and that never made sense to me before). It was that very year i programmed game AI that would chase the player in a realistic way. So yeah, math helps