Ettie Andrews Depends. It's for sure appropriate for 13-15 year olds. 12 could be a bit young depending on the child. If your nieces are sensitive maybe give to the older ones. It was an excellent novel and and exciting read. Fair warning though there is some gore, it's mild at first, gets a bit more pronounced in the end but all in all nothing worse that most novels. But I can't recommend it enough otherwise.
Katina Ages 10 or 11-15 is perfect. I really liked it! I teach 7th grade and just recommended it to my class.
Ezra This book is really good, I would recommend to anyone who can understand some action, a little confusion, and the tiniest bit gore.
Yas Of course! I'd alter it to 10, if the reader isn't that sensitive. However, your age recommendation is perfect for The Blackthorn Key.
X . I have a niece 11 of age, and she read this book and found a marvelous. I think that this book is appropriate for children 10 and up. Or 9 if they can understand. We think children find killing gruesome, but most find it adds a touch of mystery, they can take more than we normally think.
Mrs. Smith There are descriptions of killing which while not overly gruesome could be considered inappropriate for some children who are sensitive. The Ontario Library Association recommended it for the 9-12 age bracket. I read it out loud to a 9 year old and changed some vocabulary as it can be antiquated for that age and also left out some more gruesome details. I was a fairly sensitive child and likely would not have liked this book but for many children especially boys they really enjoyed it.
Janet Martin It's been nominated for an Edgar in the juvenile category and my 10 yr old grandson is loving it. I agree with Astrid Kaniele about the 10-12 target and it's definitely a boy book. It would take a pretty sophistated 8 yr old to enjoy it
Juliana I think it's a great adventure for 14-15 year olds. My library had it in the juvenile section, not the young adult and I have a problem with that. It had some violent, bloody scenes in it, totally inappropriate for the 8-12 year old kids the juvenile section is for.