I've lived in New York over sixteen years and have yet to paint a single wall in any apartment I've rented. Not because I couldn't (okay, partly because I'm lazy), but because there are so many other ways to bring color into a room: art, furnishings, curtains, rugs, lights, and accessories. Living with walls white lets you be a nimble decorator and change things around easily which can be key to a growing kid's space.
To inspire you (renters especially) I rounded up the most colorful kids rooms in our archives with white or off-white walls. Interestingly, the majority of these rooms are outside the US and 3 of 15 belong to girls named Ava!
Click through the links to see more of each room. What's your best tip for making a white room colorful?
(Images credited in original posts)