I've always liked fantasy novels in "American" settings, but I haven't read a satisfying one since Orson Scott Card's Alvin Maker books. This middle-grade novel evokes much of what makes the Card novels interesting, including a similar obsession with big families and birth order, and "uniquely American" magic. Unfortunately it fails to do what Card does successfully, which is acknowledge/incorporate the real complexity of American history and culture.
The story focuses on Eff, the thirteenth child of the title, who happens to be the twin sister of Lan, a seventh son of a seventh son. By the standards of the (Europeanish) magical system their family uses, Lan is destined to do great things and Eff is destined to "go bad". Because their extended family insists upon treating Lan like a king and Eff like a walking time bomb, the children's parents decide to move them to another town closer to the frontier, where Lan might not grow up with a swelled head, and Eff can grow up with a fresh start.
I liked the way this book focused on family dynamics; a lot of the "drama" in the story comes from just the ordinary interactions of a large family full of headstrong people. That's what kept me reading. I also liked Eff herself, who wasn't too perfect or anachronistically "modern", and yet also wasn't stupid or passive. She struck me very much as a "real" and normal character, coping with some decidedly abnormal stuff. She tackles those problems with pluck and cleverness.
Unfortunately the characters outside of the family weren't as well-realized (which is why I deducted a star). I guess this is inevitable when the family in question consists of twenty-some people... not much room to focus on the other folks in town, even though many of those people were fascinating. Eff seemed to have no friends but William, the son of the town magic snob -- I wanted to know a little more about him. I wanted to know lots more about Miss Ochiba, who seemed to have no purpose in the story other than to act as Eff's mentor (and as the only black woman in the story, she edges dangerously close to Magical Negro territory). I was also put off by the way the people who feared Eff's status as a thirteenth child were depicted as simply mean and bigoted. I wanted to know if they'd known a bad thirteenth child before, or if there was some history they were reacting to which might clarify their behavior. Were Caligula or Jack the Ripper thirteenth children, for example? Instead their objections were never explained, and these characters ended up being just one-dimensional villains. Even in a story aimed at kids, I expect more depth than this -- and after years of Harry Potter, Scott Westerfeld's books, etc., I think most kids will too.
I also deducted a star because of the worldbuilding, though I waffled on this. That's because I enjoyed a lot of it, such as the explanation of the world's three main magic systems (one corresponding to Europe, one corresponding to Asia, and one corresponding to Africa, though they all have different names here). And I loved the idea of a fantasy-alternate America populated with dragons and mammoths (!) and other "magical" wildlife. But I was actively offended by the apparent erasure of indigenous people from this America -- there's nothing on the continent but forests and animals, making for a spooky sort of Manifest Destiny message as the mostly-European settlers make their way across it. The author appears to have considered what this absence would do to her alternate America -- for example, all place-names based on Native naming have been changed (e.g. the Mississippi is now the "Mammoth river"). But this actually adds to the problem, because it suggests Native Americans contributed nothing to early American culture but names. Also, though there are a few black people present among the settlers and Asians are said to exist somewhere, there doesn't seem to have been a system of slavery (or I missed it) or labor exploitation in this world. So I can't help wondering how this alternate America has been settled so effectively. Slavery was evil, yes, but it's also an inescapable part of American history because of the desperate shortage of labor in the country's early years. There simply weren't enough Europeans to do it all, grow at such a breakneck pace, and still feed themselves -- so who did the work here? It's not just that. This world has a railroad system, but we see no Chinese people, so who laid the tracks? For that matter, where are the poor white people, struggling to eat when (at one point in the book) there's a string of crop failures? If they're mentioned, I didn't see them.
I think this is what bugs me most. The book's theme is that America is unique because of its diverse mix of cultures, yet the book fails to actually *depict* much of that.
The children and teens who this book is aimed at might not pick up on this, or they might be sufficiently dazzled by dragons!!! over the Mississippi!!! which I will admit almost distracted me. But I think a lot of kids are pretty savvy these days, and a lot of them *will* notice. I think it might leave the same bad taste in their mouths that it did me, ruining my enjoyment of an otherwise decent story. Because of that I cannot recommend this book.