"One really does want to try it from age seven, but I'm not sure how much of this stuff even I could have gotten at age seven. It'd be worth trying, though."
I fully intend to teach my children (when I eventually have them, that is) about cognitive biases and rationality from the time they are born. I think that we greatly underestimate what children are capable of understanding. (It is also possible that I am biased, since I was an unusual child and so I can't generalize my experience across all children - but even if that's true, there is at least a good chance it will work with MY children, so much the better for them.) In the future, our children might be taught concepts in their earliest books that we have not even discovered today.
Lie.
There is no reason that your Christian social network has to know you are reconsidering your position. Going forward you can work on building other networks which don't rely on your faith, and eventually you can make your beliefs public if you so choose. You can continue to grow personally, even if no one around you knows you are doing it. We all present ourselves in a different fashion depending on our audience; this is different only in magnitude.
On a related note, one of my resolutions is to do more reading, for this very reason. My own project thrives most when I get exposed to new and different ideas. There is so much knowledge out there, and so little time in which to absorb it. Someone could have already thought of the next critical piece I need to move forward, and I wouldn't even know it yet.