The Golden Compass OR Northern Lights
by Philip Pullman
I first read this around 2000. When I got to the second season of the recent TV Series, I began to wonder about the accuracy and decided to re-read the books.
Our heroine is the headstrong and wild Lyra Belacqua, who is 12 years old and lives in an alternative version of Oxford, England (Pullman's home town). Everyone in her world has a "dæmon," an intelligent animal that's an external soul. Lyra is an orphan, left to be raised at the university by the professors. Shortly after the book begins, her uncle Lord Asriel (who placed her in Oxford) shows up. First, he essentially encourages her to further run wild by exploring more of Oxford, and then he has a meeting with the college's Master who attempts to poison him - but Lyra warns him. Shortly after that, her best friend Roger disappears, and she's sent away from Oxford.
As the story proceeds, Lyra finds that Roger's disappearance is part of a larger group of events, with many young children kidnapped by "the Gobblers." She joins a group going to save those children, and because of a gift given her by the college Master and her own intelligence and determination, she becomes central to the process.
But there's more going on here: her world is dominated by the Magisterium, commonly called "the Church." The parallels to the Catholic Church are clear, although the Magisterium is far more powerful (the Master of Oxford attempted to poison Lord Asriel because his work is "heretical" and thus very damaging to the university).
If it sounds weird ... well, it is. But it's also well written and lovely. And one of the things I loved about it from the first time I read it is how our 12 year old heroine changes the world. In most children's books, young heroines go out to change the world - and they do it, either alone, or with the help of other children. Not Lyra: not that she's weak, we know how intelligent and strong-willed she is. But she has to achieve huge things, which couldn't be done without adult help. And she has that - partly because of the adults care about this willful, intelligent, morally uncorrupted young woman, but also because of destiny: she's named in a prophecy. And I find a young woman changing the world with a bunch of adults behind her far more believable than a young woman doing it entirely alone.
The book ends somewhat unsatisfactorily with a death and Lyra stepping into an entirely different world ... but first we'd been warned there were other worlds, and second this is a long-complete trilogy so a lead-in to the next book is expected.