Parents need to know that this story has, like the Norse mythology upon which it's based, moments of rather grim violence. There's also some swearing and references to drinking, drunkenness, and pipe smoking.
Violence:Lots of fantasy violence, some a bit gory. A man is beaten into unconsciousness, hit in the shoulder by a crossbolt, stabbed, and slashed; a wolf rips out a man's throat. The characters experience gruesome visions of torment in the Underworld.
I have just found a personal favorite!!! Totally AMA-zing!!!! Maddy is an incredibly real character, I can't believe this isn't a biography -- only if this new and intriguing kind of magic introduced by Ms. Joanne Harris exists of course! I definitely felt like I'd known Maddy my whole life by the time I was done reading this. Runemarks is going to be more interesting to kids who have read and are interested in Norse mythology. I personally was extremely glad that I am very familiar with it. I did find it quite obvious who some characters (namely "One-Eye" and "Lucky" as they claim to be called) were going to be. So in that case part of the surprise was gone. I feel that although the main character, Maddy, is female, four other important supporting characters -"One-Eye", "Lucky", Mimar, or "The Whisperer", and Sugar, the goblin -are male, so I feel that both boys and girls will like it. I particularly enjoyed how the author fit in so many characters from Norse mythology, but I wish she had taken more time developing most of them.
For those with an interest in Norse mythology, this could be a lot of fun. For others, it may be just a bit too long and insufficiently engaging. To my taste, less would have been more in terms of using fewer of the Norse gods but developing their characters more -- as it is, there are lots of the gods but only a few get enough time to get much of a feel for their characters, and the rest just end up seeming like rather irritatingly quarrelsome flat figures. So while interesting, I didn't find the book fully satisfying. But there's where more familiarity with Norse mythology would probably aid in enjoyment. There's not much to be concerned about for ages 9 or 10 or so: the most bothersome aspect being the extensive visions of the torments of the dead in the underworld -- that does get pretty nasty. Other than that, the violence is not too much -- fairly typical for fantasy. And I hardly noticed the drinking or smoking the CSM reviewer mentions. So I'll say okay for ages 10+, though I think at the younger end of that range it would be only readers with particular interest who'd enjoy it.