I recently did this one with motorcycles for Quilts for Kids. There are lots of fabrics with sports themes, outdoorsy types, martial arts, hamburgers & hotdogs, etc. even money! and playing cards. Find out what they are into. For one of my sons I made a rail fence using various shades of denim from his and his brothers' old jeans. He was about 12yrs old at the time. He still has it and he is now 40!