The first thing I noticed when I set out to write this entry was how "The List" and the book's publisher (my copy is a Puffin Modern Classic) recommend this book for completely different age groups. If you haven't read Jane Yolen's The Devil's Arithmetic (I hadn't) or don't know what it's about (I didn't), the book is about the Holocaust and the age group determination mainly has to do with this subject matter rather than any potential reading difficulties. Alright, maybe some of the Yiddish would trip up a young reader, but that's what dictionaries or Jewish bosses are for! My Jewish boss is conspicuously absent on this sunny day of work though...
"The List" recommends this title for children/young adults 12 and up, but the publisher stamps it with an 8 and up. Deciding when this book is appropriate depends on the child's ability to handle some pretty traumatizing history.
Quick plot summary: Hannah is a 12 year old girl who doesn't understand why remembering the past is such a big deal. She's bored with her family's Passover celebrations and is jealous that her friends get to eat jellybeans on Easter (apparently this book was written before Reese's Peanut Butter Eggs were the big Easter hit) and basically have fun. But while Hannah is going through one of her family's rituals, she's suddenly transported straight into the 1940s, where she is called Chaya and witnesses firsthand the horrors of the Holocaust. At first, she is able to hold onto her memories, but soon her new present overwhelms her and she needs to live [survive] in the [horrible] moment until she learns why it is so important to remember her family's past.
I wasn't a huge fan of Yolen's Briar Rose, which has a similar topic, but I loved The Devil's Arithmetic. Having Hannah, a girl from the present, directly thrown into the action makes a great impact. The immediacy of the action makes the material easier to digest, as opposed to Briar Rose when the main character just listens to a story. Even the idea of a present day girl going back in time adds a lot to this book. Books that simply take place during this time period can hinder a reader if they don't already possess background knowledge. This setup helps a reader new to this topic understand the history before diving in.
So who's right with the age recommendation? No one is right. Everyone is different. But if I had to place this book somewhere, I'd say it'd fit nicely in a 5th-6th grade history curriculum. There are so many books with similar topics for this age range - - Number the Stars, The Boy in the Striped Pyjamas, Milkweed, etc. - - that it'd be easy to assign one book to a group of students and have them present it to the class along with a history lesson that ties into their book's theme(s). The book would also be a great gateway into this topic, especially because a lot of children either don't know the history or don't understand why something that happened years ago could still be so painful.