Groosham Grange - Two Books In One! (Anthony Horowitz)

David quickly discovers that his new school, Groosham Grange, is a very weird place indeed. New pupils sign their names in blood; the French teacher disappears every full moon and the assistant headmaster keeps something very chilling in his room... And that's just the first year. In his second year, David is on a course to win the Unholy Grail – but something is trying to stop him from winning.