Words and Children

I had seen this study that Joanne Jacobs cites, but something struck me as amiss:

"Research has shown that greater verbal interaction between parents and young children improves students' performance on standardized tests," Farkas says. "By the age of three, professional parents had spoken an estimated 35 million words to their children, working- and middle-class had spoken about 20 million words, and lower-class parents had only spoken about 10 million words."

These families differed not only in the total number of words spoken, but also in the number of different vocabulary words used in these conversations. These differences had strong effects on the vocabulary knowledge developed by the children in these families.

"By 18 to 20 months, the vocabulary growth trajectories of the children of professional parents had already accelerated beyond those of other children," Farkas adds. According to his research, there seems to be both a social class, and controlling for class, a Black-White difference in children's oral vocabulary growth from infancy to adolescence. Preschool vocabulary knowledge is a strong predictor of reading performance in early elementary school, and early elementary reading performance is a strong predictor of later school performance generally.

35 million words? By age 3? The math doesn't add up there. That amounts to 11.67 million words per year, or 31,963 words per day, or 2,283 words per hour for fourteen waking hours, or 38 words per minute.

So professional parents really speak to their children at the rate of 38 words per minute for every minute of 14 hours per day, every day until age 3? I don't believe that for a minute. No one talks that much.

Then I'm unsure about the purported difference between "professional" parents and "lower-class" parents. I'd wonder if the real difference is the total vocabulary, as compared to the sheer number of words. That is, more educated parents might use a wider range of words, but aren't any more verbose. Conversely, maybe lower-class parents speak just about as much, but use a more limited vocabulary. These are just hunches, mind you; I don't actually know for sure what the facts are here.

UPDATE: I forgot that many parents put their children in daycare. Whatever the merits of this choice, they obviously don't have as much time to fit in those 35 million words. Doing the math, 35 millions words by three years works out to 224,423 words per week. If the parents see the children for 2.5 waking hours on weekdays and 14 waking hours on the weekends, that is only 40.5 hours per week. Allowing the parents half an hour per week of leisure time to themselves, they'd have to spend the other 40 hours speaking to their children at a rate of 5,611 words per hour, or 1.56 words per second, all at a non-stop pace.

Now maybe there are parents who spend every waking second talking like an auctioneer. But this can't possibly be the average.