Also, I'm going to link this, because I still believe it's really more about this stuff than Kumon:

http://www.childrenofthecode.org/interviews/risley.htm


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What we found is that the more talkative parents, like the parents with college educations and the professionals like doctors and lawyers are hearing about 2,100 words an hour, hour after hour after hour. The children of welfare families were hearing about 600 words and hour, hour after hour after hour.

So we said, "All right, what was the difference in language input, in language experience, of the language they heard, words they heard in meaningful contexts?" We estimated that the average child, figuring 100 hours a week, by the time they were four, heard thirty million words addressed to them.

But the children of professional parents -- I mean, talkative families and college educated -- heard forty-eight million words addressed to them by the time they're four.

Children in welfare families who were taciturn heard thirteen million words addressed to them by the time they were four.

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ow, the interesting thing is that when look at the amount of talking the parents are doing, and the amount of extra talk they're doing over and above business talk, nothing is leftover relating to socioeconomic status. It accounts for all the variance.

In other words, some working poor people talked a lot to their kids and their kids did really well. Some affluent business people talked very little to their kids and their kids did very poorly. You see what I'm saying.

David Boulton: Totally. And it corresponds, as we said earlier, to information coming from the neurosciences. It makes sense.

Dr. Todd Risley: Absolutely. And there's nothing left for race either. Remember, we stratified by African-American, and nothing left. All the variation in outcomes are taken up by amount of talking, the amount of talking in the family to the babies before age three.