Teens, Tweens, and Secret Reading

After our discussion about books as mirrors or windows at different stages of life, I'm setting up a tentative hypothesis. Ready? Here it is:

Elementary-aged kids and upper high-schoolers are more open to fiction with protagonists who are markedly different than they are when it comes to race, class, or nationality.

During the early adolescence, fifth through ninth grade, most young readers buzz about and share books featuring protagonists they hope to resemble. Also, if everybody's reading...