Our teenage nieces and nephews all got traditional, simple patterns using fabrics related to their interests (motorcycles, music, guitars, "retro" ) and they all loved them. We used alternating 4-patch, D9P, Friendship Star, and YBR.
Also tonight I purchased a book at Jo-Ann called "City Quilts." The designs are very modern-looking and use solid or near-solid fabrics. I thought they would make good guy quilts, but I think many teenagers would enjoy them too.
Merry Christmas.
Darren