When Kendall was 13, I painted her room like this. (Prior to that, it was baby blue for eight years, so she was due.) I bought the bed from Craigslist and painted it white.
Recently, she decided she was ready for something a little more mature. Her room also gets a lot of light, so it can handle dark colors; we picked the bedding and then chose this milk chocolate color...
Soon, she'll have shelving above her desk. Her dresser (a tall, older type) is now inside the closet (and the curtain is leftover from the previous decor.)
Of course, the room still needs some accessories and stuff for the walls, but Kendall loves it and has thanked me many, many times. The old bed is gone, and she finally has a new mattress (to replace a very old, mushy one.) She did encourage me to tuck her in tonight, and she exclaimed that she felt "like a princess." So yes, the pain was worth it.
Never mind that her mom is a little sad to say goodbye to the kid-stuff. It's part of life, right?