"Harry Potter and the Prisoner of Azkaban" was a fantastic book. It was very interesting and moving. There are two things I liked in particular. First, the opening chapter. It was a GREAT recap chapter. It's not like Animorphs or Baby-Sitters Club, where the author just gives a huge exposition dump on you. The book actually worked the recap into a short story of Harry opening his birthday presents. It was nice.
The other thing I liked was the sequence in the Shrieking Shack, which was extra-long and extra-good. I reread it so much, the pages of my book fell out. Unless I'm remembering wrong, we have a chapter where our heroes confront Sirius Black, a chapter where Snape appears, a chapter with Sirius after that, and a fourth chapter, where the real culprit is revealed. Four chapters, which was mostly characters standing around and talking. The conversation was super interesting, with all of its twists and turns, and it's a shame the movie cut out pretty much all of it.
But then there was another twist: time travel! I liked that idea, of going back through the interesting stuff. Sadly, our heroes decided to play it safe and NOT change the timeline at all. I didn't like that so much, because the way it played out, they spent most of the three hours sitting around, waiting for everyone to leave the Shrieking Shack.
I liked Professor Lupin. It was good for Harry to have a new teacher who isn't crazy for once.