How to introduce GTD to kids?

Hi,
I'm a father of 4 children: 9, 7, 5 and 3 year old. I would like to introduce GTD to, at least, my two older kids. Do you have any tips for startup?
 
I really like the second link.

In my opinion, full-fledged GTD is a bit of overkill for most preteen kids. They just don't have 50 different Projects going at once. But you certainly can introduce and encourage GTD principles, including inboxes, hard edges, 50,000-feet thinking, and the 2-minute rule.
 
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