If you haven't read Wonder by R.J. Palacio, you are missing out. It's about a boy with a facial deformity who has been homeschooled all his life and starts fifth grade at a private school. The story is told from different points of view including Auggie, his sister, his friends, and a few other characters.
A central character in the book is Julian, who bullies Auggie throughout the book and at the end(show spoiler)
But we never hear from Julian throughout the book and never know why he did the things he did.
It is a short book made up of a series of chapters which follow most of the book Wonder and reveals why Julian did what he did to Auggie. I thought his motivation for the bullying was good, since that's not what I would have guessed. The reactions of his parents were also interesting since you heard a bit about them in the book, but I don't think we met them.
The best part was the end when Julian goes to visit his grandmother for the summer and learns the story of where his father's name (which he shares) came from.
If you haven't read Wonder, you may enjoy the book, but you really have to be familiar with it to enjoy it.