As you may have gathered from the cover art, The Penderwicks is a sweet little book:
Now, if Rosalind had been the first to discover that tunnel, she would have noticed that it was too neatly trimmed and pricker-free to be there by mistake, and she would have figured that someone used it often and that the someone probably wasn't Mrs. Tifton. If Jane had been the first, she, too, would have realized that natural forces hadn't formed the tunnel. Her explanation for it would have been nonsense--an escape route for convicts on the run or talking badgers--but at least she would have thought about it. But this was Skye. She only thought, I need a way through the hedge, and here it is. And then she plunged.
The four Penderwick sisters, along with their father and their beloved dog, Hound, rent a cottage in the Berkshires for a few weeks in the summer. While there, they have many wholesome and charming adventures including running from an angry bull, trying to catch a rabbit that Batty, the youngest Penderwick, accidentally let out, and getting muddy and/or wet on a daily basis.
They spend a lot of time with the handsome (and much older) Cagney the gardener, Churchie the housekeeper, and Jeffrey, the only son of the cottage's owner, Mrs. Tifton. Mrs. Tifton is so horrible and frightening that one of the girls likens her to Narnia's White Witch. Her boyfriend, Dexter, is a smarm-fest who wants to send Jeffrey to a military academy.
Here's a question: These girls are very well-read -- they reference Nesbit's Bastable family, Edward Eager, C. S. Lewis, Katherine Paterson and others -- but they don't recognize the garden statue of a man "wrapped in a bedsheet and holding a thunderbolt over his head" as Zeus? That didn't seem right. Granted, it was Skye (she's the math-oriented sister) who first noticed it, but surely one of the others would have recognized him?
Also, Mrs. Tifton was just too mean. I was grateful that there wasn't some huge schmaltzy reunion all-is-forgive-everything-was-a-huge-misunderstanding scene, but I really thought she was a tad over the top. Those are just little annoyances -- over all, the book was completely enjoyable.
So. If you've read all of the Enright books and the non-fantasy Nesbit books, this would be a logical step in that progression. I don't think it was on the same level, and I don't think there was anything particularly new and/or fresh about it, but I adore the Melendys and the Bastables, so I might not be being objective. (And I know I'm not being objective in regards to the National Book Award. I really just don't get it.)