My boys shared a room up until oldest started 8th grade, youngest started 6th. They had this room since they were 3 & 5.
13 and 11 is when they got own rooms, rid of bunks. I let them design their rooms. I took them to paint store. My older one (now 14) wanted white walls with one black chalkboard wall. A new cool light fixture to replace ugly ceiling fan. Rug over part of wood floor navy/grey/white bold stripes. Espresso book cases, cool L-shaped desk. It has a minimalist modern look. I like it better than my master.
My younger one picked a brighter pool color for walls, and white comforter, sort of a birch wood/distressed colored loft/dresser. We used white curtains with light grey border. His walls are a bit bright so I don’t know if they will last as he ages, but the older one can have his room until college and beyond.
It was pretty funny when at 13-he said “mom, my rug and bed spread have race cars on them. It’s embarrassing

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