Maria Snyder was the author of our recent book club book (Poison Study). Her fourth book in that series, Storm Glass, begins a new direction by following a different protagonist. Opal can do magic with glass, but isn't sure how much use she or her magic really is. Although she has adventures (the usual -- kidnapping, battling evil magicians, foiling jewel forgers, etc.), the story arc really concentrates on her growing self-acceptance and self-confidence, complicated by the trauma of her experiences in the earlier books.
Young Adult is a relatively new genre, and definitions of it vary depending on which book store or library is shelving the books. Lately it seems to mean "Older Children" or "Late Teen," with books aimed at about the high school level, sometimes even junior high. But to me, the genre means books where the characters are learning to be adults, and that is where this book fits. Opal is young, maybe twenty or so, and she is deciding how she wants to live. She's at a magic school, which gives her some of the leeway college gives modern kids -- out of the family shell, but not really independent yet. She wonders what kind of relationship she wants, what kind of career to aspire to, what kind of trust to have for herself.
And of course, she gets to do it with magic, which makes things even more fun. But her approach is an adult one, even if a naive and new adult. Not great literature maybe, but a good solid read. B
PS. My bookmark for this book was my movie stub from New Moon, the latest Twilight book-to-movie. There's an example of Young Adult meaning "Older Child" -- did anyone get the sense that Bella was making adult choices? Because I sure didn't, even in the last book.