Folks in children's literature have been struggling for awhile now with how people of different races are represented (although white people haven't been the topic as much as they should be) and who should get to represent whom. But a couple of recent articles suggest that there are such basic issues with who is represented at all that the various lit-theory inspired arguments may, in fact, be jumping the gun.
Check out this article about a study-in-progress finding only one Latino character in a decade of transitional chapter books.
But also note the title "Urban." I read this expecting something else, which was more in line with this definition of "urban," with an emphasis on hip-hop and African American experience. Which suggests that we still haven't achieved a multi-racial society that knows how to talk about race consistently.