I am currently reading this little, entry level, book on reading the Bible intelligently written by the Australian Biblical scholar Robyn J Whitaker.  It's a nice accessible read, aimed espeically at those who come from a conservative theological background - which is the author's own story.  She holds together keen critical insights with a profound love of scripture.  Definitely one to consider sharing with teenagers or with adults who have never come across the concepts she shares which range from authority and (in)errancy to genre, the canon, and interpretation.  It's mostly stuff I've known since my teens (the back of the original Good News Bible was remarkable helpful in this regard!) and is great as a primer for those considering serious Bible study, preaching or ordination training.