I think three books come to mind right away for me, and I'm not sure they're perfect for your purposes, but for some reason you've caused me to ponder on them --
She's Come Undone, by Wally Lamb, who is just excellent at getting into the mind of a teenager, and a girl at that.
The Book Thief, by Markus Zusak, a brilliant writer who makes you think from another point of view in Nazi Germany.
The Center of Everything, by Laura Moriarty, about a teenage girl in the middle of Kansas who has a lot on her plate.
When it comes to ethics, I loved Complications, by Atul Gawande, who is amazing, but it's a medical book written by a surgeon here at Harvard (not sure it's what you're looking for). And for philosophy, that's just a tough one, period. What about Sophie's World, by Jostein Gaarder? It's an oldie, but a goody!!
You should be able to find all of these on Amazon:)