Harry Potter and the Chamber of Secrets (by J. K. Rowling)

Stuck with awful relatives for the summer, Harry is relieved to be rescued by his friend, Ron, and Ron's brothers in a flying car. Back at Hogwarts, Harry discovers that the legendary Chamber of Secrets has been opened by the mysterious Heir of Slytherin, releasing a monster who prowls the halls of the school turning mudbloods (those with non-magic parents) to stone. Suspicion soon falls on Harry, who bears more than a passing similarity to Slytherin, including being a Parseltongue (one with the ability to converse with snakes). But Harry and his friends, Ron and Hermione, have even more reasons to try to track down the real Heir and stop the monster: Ron's little sister has disappeared, and Harry's friend, the gamekeeper Hagrid, may be more involved than he's letting on. 

Though the formula is similar to the first book, this well-written, exciting sequel keeps kids glued to the page. It breaks no new ground in the series, but the plot is a riveting thrill ride filled with giant man-eating spiders, a ghost who lurks in the girls' bathroom, secret underground vaults, time travel, magical-transformation potions, the near death of several major and minor characters, and a climactic confrontation with the greatest evil wizard of them all, Voldemort. J.K. Rowling excels at twists, turns, and surprises, and many will find the identity of the person who opened the Chamber a complete surprise.