For your teen who loves a good mystery that isn't too gory or sexual:
I'm always wanting to read a Sherlock Holmes YA novel. I have a bit of a fascination with Sherlock Holmes, probably thanks to the Young Sherlock Holmes movie that came out forever ago. There are quite a few young Sherlock Holmes series out there, but I haven't liked any of them. Until now.
This series revolves around the niece of Sherlock Holmes who teams up with the niece of Bram Stoker (she's a vampire hunter, but there weren't any vampires in this book) to solve a mystery. I really, really liked Sherlock Holme's niece in this book. I related to her, so while the mystery was good, I kept on reading for the character. I had to jump ahead to find out the ending because of time limitations (I know, I know! Evil, some may say!), but I still went back to read what I'd missed.
For me, that's saying something.
Ages 12 and up.