Here's a quick list:
1. Apparently Karen Thompson Walker got a huge advance to write The Age of Miracles. As her (somewhat precious) jacket bio explains, she wrote the book in the early mornings before going to her job as a book editor, and it seems to have prepared her well: The Age of Miracles—about a world changed when the earth starts turning more slowly, told by an 11-year-old-girl—is strange, and incredibly moving. Like When You Reach Me, it's a surprising, beautifully written story about a middle-school-aged girl with some completely uncheesy science-fiction elements.
2. The Innocents got its young female author lots of glamorous press as well. Back when I wanted to write fiction, and was, shall we say, weak on plot, I wish I'd had Francesca Segal's idea: update The Age of Innocence, and set it in a contemporary upper-middle-class Jewish enclave London. (She's also got connections and genetics on her side.) Despite an ending I knew and some overly cute updating, the book is funny and familiar.
3. Holes is by no means new, but I've just now read it (on Charlie's recommendation) and watched it, and I loved both versions. The movie spells things out a bit more clearly than the book; I preferred the book's more elliptical way of telling the story, but maybe the obviousness is good for kids. Either way, I wish I knew how Louis Sachar pulled off such a sweet, funny, utterly non-preachy book about racism, bullying, honesty, and friendship. Seriously.