I never got the talk, well not in any formal manner atleast, i think it was one of those it was creeping up at the dinner table and my brother and I (15 months younger than me) brushed it off with a "yeah yeah we've got the idea already!"
I would be insistent on being smart about it, and not getting tied down to one girl. you only live once!
and like mentioned above, go take a drive or something so you can sit sidebyside, I learned this in my peer tutoring class, it's always more comfortable for the student when you position yourself as a friend, not an enforcer or bigger person (by standing or facing them)
Also, Miata would definitely be a good answer once he turns 16, i know the backseat got me into trouble...