I read this when it first came out and not since. All I could remember was that there are somehow separate stories that all make sense together, but nothing about the characters or the story. Well, it turns out that that is an accurate memory. 4 children are part of a quiz bowl type team and their teacher, Mrs. Olinsky, is always evasive about how she picked these 4. Parts of the narrative are the story as it is happening now-a quiz bowl event with questions. But each question takes us back to a story from the point of view of one of the children, and a story that tells us more about that individual. And indeed, all the children are somehow connected, through a retirement village in Florida, grandparents, dentists, families, and school.
I listened to this on audio with my daughter and we both loved it. I do like a story where you can see all the pieces fitting together.