ReReading for the 6th time 'Bloody Jack: Being the Curious Misadventures of Jacky 'Mary' Faber Ship's Boy' of the 'Bloody Jack Series' by L.A Meyer Very VERY good book, about a homeless girl in the late 1800's that dresses as a boy to join the royal navel. The series follows her from age 12 to 17 (and on hopefully more books to come.)
The first book in the series is a bit hard to follow for the first few chapters as its written from Jacky's point of view and she has a heavy accent but it only gets better! Someone please read it! Its my obsession, one of the best series I've read! 10 books in the series so far.
Also I'd suggest looking into these, they're all sort of aimed towards teens to young adult, but are very good. Lots of adventure and good twists.
Uglies by Scott Westerfeld
Leviathan by Scott Westerfeld (steam punk alert!)
Maze Runner by James Dashner
Battle Royale (UnEdited Version) by Koushun Takami (this is what they think Hunger Games is based off)
Unwind by Neal Shusterman
SkinJacker Trilogy by Neal Shusterman
ANYTHING that is by Tamora Pierce
Okay I am done gushing....I love books especially adventure, and dystopian. The Uglies Trilogy +1, has a bit of confusing romance as the character grows. Bloody Jack has a good bit of romance but its done very nicely. Jacky is a STRONG female character that I think more young girls should read about.