My wife and I loved the Shadow Children series, by Margaret Haddix. My comments on that were what prompted Adam's recommendation of Hunger Games.
I also suggest The City of Ember, People of Sparks, and The Diamond of Darkhold (not City of Yonwood, which was mostly lame).
I also suggest The City of Ember, People of Sparks, and The Diamond of Darkhold (not City of Yonwood, which was mostly lame).