You could find sporting fabric for all sports or his favorite sport, then a simple 9 patch alternating with a square, either plain, the size of the 9-patch, or you could snowball the square. I made my DS an Irish Chain quilt in black and bright blue when he was about 11, and the quilt followed him every time he left home and every time he returned (I had boomerang kids, they kept returning- LOL). You could do an Irish chain in 2 colors, then use sports material on the back of t he quilt.