Anyone looking for a fun, age-appropriate fantasy series for a girl in third or fourth grade should seriously consider the Sisters 8 books, by Lauren Baratz-Logsted (with Greg Logsted and Jacki Logsted). I can't make that "definitely consider", because Zinnia's Zaniness, the eighth, and penultimate, book of the series (Sandpiper, 2011, 128 pages), is the only one I've read. It was nominated for the Cybils Awards in middle grade sci fi/fantasy, for which I am a panelist. New to the series though I was, I found Zinnia's story to be a pleasantly diverting read.
The Sisters Eight are eight-year-old octuplets, each of whom develops in turn a magical power, and receives a special gift. But there's a catch. Their parents are missing--and until each girl gets her power and her gift, they won't know what's happened to their mom and dad. Annie, Durinda, Georgia, Jackie, Marcia, Petal, and Rebecca have all had their turn. Poor Annie, the oldest, has the gift of being able to think like an adult, but the other sisters have more interesting powers--freezing people, invisibility, super speed, etc. Now the girls are waiting for the youngest and the smallest sister, Zinnia, to manifest her own power.
And in the meantime, kindly neighbors are taking the family on a seaside vacation. There, in a somewhat dingy vacation cottage (hotels aren't an option, since not only are they are rather large group, they've brought their kittens with them), they'll bicker, play, worry, and meet a mysterious boy....and Zinnia will reveal her own special gift.
The adventures and the magic aren't all that Exciting--it's the relationships between the sisters that gets the most page time (which is fine with me, sisterly relationships being something I have my own considerable experience with!). That being said, the characterization of the sisters in general isn't all that deep--each has a few trademarks that are brought forward in turn; enough so that they can be distinguished, but not so as to make them come alive to a new reader of the series. But Zinnia, in this, her own book, had the spotlight shown on her, and became quite real to me--probably this happens to the other sisters in their own books.
This isn't a series I'd recommend to the grown-up readers of my blog, but for eight year old (or so) girls who love mysteries and magic and kittens, I think it's a pretty safe bet.
Disclaimer: review copy received from the publisher for Cybils consideration.