I have to disagree with R. Fry. I don't think it overdoes political correctness. As a parent who was at one point bringing up a small child in a tiny urban flat it was extremely refreshing to find a children's book that didn't represent a world of white middle class children living in a pristine suburbia with names like George, James and Cameron. Finally, a modern book for kids, about kids, that doesn't shut a mock-Victorian leaded-light door in the face of the ordinary child.
Besides the political issues, it is a realistic portrayal of young children learning to share and work together, and it's really fun!