Let them choose their color, so they could express all their feelings and in a way impress their friends by following the latest trends.
If your boy is a fan of football, which is common among many boys at this growing age, paint his wall all red and let him post pictures of his favorite Arsenal players for some drift. Storage solutions are a must when designing your boy’s room.
At this age, he would need an alarming number of stuff to gather and homework folders to accommodate. If the vertical space is enough; then create paneled boxes for storing and creating a stylish sitting place over it.
You could even leave some space and then again start paneling boxes from the ceiling for a further aesthetic and utilitarian feel. Replace his bed with a sofa bed and contrast the cushions with the closet unit and the study table.