With so many options on the market and after some extensive research, we purchased this high sleeper bed for our 12 year old daughter. 
It is excellent quality and we like the whitewash wood. Very strong and sturdy. The futon cushions are thick and comfy, the shelving provides loads of storage for her books and the desk is quite big. 
We swapped the futon and desk around from the picture to suit the room, so that flexibility is great. 
This will suit her for many years to come I reckon. Highly recommended.