I think that the curve apparently flattens as they learn more and more about the world and develop broader and more varied interests. Sort of like the way that a river meanders as it reaches its floodplain.
I also think that development can go stealth as our kids age. My kids were much less interested in talking to me about all their amazing non-stop questions once they hit late elementary school - so I kinda miss all the early developmental explosions.
OTOH, we still have absolutely fascinating discussions - I just have to start them much more of the time now
polarbear
