I've found that my DS8 doesn't ever ask a question unless he has already thought through an answer. So I usually turn the question back on him and ask him what he thinks. That at least buys me a few minutes to rack my sleep-deprived brain for some semblance of an answer. smile

The link I provided above for the String Ducky is really pretty simplistic. It explains string theory in terms of a cute rubber ducky. Very kid friendly.

Mom to DS12 and DD3