In this volume, a creature is set loose in Hogwarts that preys on the children of muggle - or non-magical - parents, known as "mudbloods." As more students are found petrified, Harry goes searching for a secret chamber rumoured to have been built by the original founder of House Slytherin. 
 The main theme of this volume seems to be identity, and whether it is something a person is given or something they must construct for themselves. Hermione, for example, is targeted because of her status as a "mudblood," and yet she is clearly the most gifted witch in her class. Harry finds out that he somehow absorbed a part of Voldemort when his parents were killed - a part that the Sorting Hat had identified when it had tried to put him into Slytherin in The Philosopher's Stone - but that he doesn't have to let this define him. 
 The series is written for children, but the scene in which Harry&co. find Mrs Norris made me realize that this didn't mean that Rowling would be pulling her punches. This was a truly scary scene and, while Mrs Norris turned out not to be dead, it helped to prepare me for some of the tragedies to come in later volumes. 
 The Chamber of Secrets is full of themes that are artfully set up for parents to discuss with their kids. The issue of racism, of course, is central to the book. Also, the idea of not simply accepting what one reads as fact even if it's labelled as such. Lockheart's books, while supposedly of his exploits, turn out to be lies. And, of course, Tom Riddle's diary serves as a great lesson in net safety. 
 I didn't think it would happen, but I can feel myself turning into one of those "Potter-heads" I've spent the last couple years making fun of!