"Oh, there are any number of useful things," Camilla said vaguely. She was beginning to feel a little anxious; Charles hadn't shown up at all, which was the whole reason she'd been lurking about Ravenclaw, since she had things to give him that she'd promised to bring, and the longer she was here, the likelier Henry would start to wonder things she'd rather him not wonder. "You should practice, though. And you should look into textbooks. Most people here spend time in independent study, since classes aren't offered all too regularly." She glanced about again.