The Volokh Conspiracy
Mostly law professors | Sometimes contrarian | Often libertarian | Always independent
As I mentioned a few years ago, I love Naomi Novik's Temeraire books. Horatio Hornblower with dragons about summarizes the general theme (the lead character is quite Hornblower-like), but of course the trick is in the execution, and I found the books to be very well done. Note also that this is fairly realistic fantasy, as fantasy goes. There's no magic or any other fantasy element, besides the dragons, and the writer tries hard (and successfully) to create a world that one could imagine being our own, as of 1800, with this one extra element.
The series just concluded with the ninth book, League of Dragons, which is one of my favorites within the series— the two other best ones are the first, "His Majesty's Dragon," partly because it's the freshest, and the fifth, "Victory of Eagles," which seemed to me to have the most complex character development. You have to read the books in order, though, and all are worth reading.
This is also one of the few series that my wife, my then-10-year-old son, and I have all enjoyed; I gave a copy to a 12-year-old daughter of a friend of mine, and my friend reports that the daughter is much enjoying it, too.
The books are definitely written for adults, with adult language and grown-up themes (I hesitate to say "adult themes," because that often means something different). But they are accessible to children, too. There is certainly plenty of violence (Horatio Hornblower! And dragons!), and references to sex, just because these are adult characters living adult lives; and some elements may be hard to understand if one doesn't understand that adults have sex, that this has certain possible consequences, and that this was perceived in a certain way in the early 1800s. Still, I highly recommend the series for both adults and children 10 and older.