When my nieces moved to a new house, I wanted to give them a room that could grow with them from little girl to preteen. The older girl wanted a jungle room and the younger wanted a princess theme, so I compromised with an enchanted forest with a faerie tale castle in the clouds and jungle animals lounging in the “trees.” I used muted colors to avoid the cartoon-y look children’s murals can get, and used abstracted shapes instead of fully realized forms. You can see the entire transformation from 1980s wallpapered duck room to its current state here: http://hadesarrow.com/blog/2011/03/14/nice-niece-bedroom