I found out about Kira-Kira because Michael had to read it for the children's literature class he is currently taking. The book, which is by Cynthia Kadohata, won the Newberry Medal in 2005.
Kira-Kira is about a Japanese-American family in the 1950s and 1960s. The need for work forces them to move to Georgia, where they encounter both overt and subtle racism (i.e. segregation, shunning, etc.). Both parents work a lot in order to save enough to buy a house, putting up with really awful working conditions, such as the mother having to wear a pad because the factory doesn't allow them unscheduled bathroom breaks. Then the oldest daughter gets very sick, which is more than the already-maxxed out family can easily manage.
The book is interesting because it describes a lot of injustice, but from the younger daughter's point of view. She doesn't really understand the big picture of issues such as racism and labor abuses, though of course some readers will.
Reading Kira-Kira, you can tell why it won the Newberry Medal. In fact, it reminds me a lot of Bridge to Terabithia, which won the award in 1978. I don't want to say anymore because I don't want to spoil it for anyone, but if you read it I'm sure you'll pick up on the similarities, too.