This thread is kind of Onion-esque (I mean that nicely--look what happens when a bunch of gifted adults attack a problem from their own preferred perspectives).

I really like this:
http://www.possibilityoftoday.com/wp-content/uploads/2011/06/Slide1.jpg

This is really process oriented. I bet it would appeal to a rational child's logical thinking. Ideas about "what to do if there's something you can" include the statistics, facts, preparedness, etc. If they still had trouble with the "how not to worry," part--that's more likely to be anxiety.

I'm sure there are dozens of holes in the logic (but don't care, since am all feely), I still think it's complex enough to be of interest, and not overwhelming.