I think that Chris and Charles would be very good candidates for Christian Apologetics. As first sentence is this study on Wikipedia states "Christian apologetics is a field of Christian theology that aims to present a rational basis for the Christian faith, defend the faith against objections, and expose the perceived flaws of other world views." Just because any of us are Christians doesn't mean we should believe just for the sake of believing. I used to listen to radio programs on my way home from work with some teachers on this. It might be a pretty interesting study for you both. When I get really into my questioning modes I would find more information in these searches. I haven't had as much time since the kids as I used to so I don't really remember as much of the reasons. I am sure you are both computer savvy so could find something.