I have to give a plug for a great new book released by Catholic Answers called "The Truth is Out There". It's a graphic novel that follows the adventures of two eccentric characters, Brendan and Erc, as they travel space while debating fundamental philosophical and theological issues: why do we exist? Is there a God? Is there any right or wrong?
I gave it to my teenage boys, and they were through with it in 24 hours and loved it. It's a great book to share with teens, especially in this culture of "New Atheism" that thinks Socrates, Plato, and Aristotle were just "idiots."