fair enough. Though I think I was the one pushing the more causal reading; the study itself seemed to caution against that and simply state a correlation (adding the equally problematic causal factors of video games and quick editing on TV[zzzz]). Still, even if it is simply a result of other factors (boredom at the irrelevance of schooling among the lower classes, etc.--a fairly problematic assumption in itself) noting the extra prevalance of a neurotoxin in those kids urine isn't something to simply shrug off as an irrelevant correlation. I would also think that there would be some sort of control in terms of class, race, gender, etc. in an experiment like this (though maybe I'm being too generous) making the simple disregard of the correlation less appropriate.
On the other hand, I think it is a problematic assumption that kids in higher socioeconomic strata necessarily eat organic food--much less that they wouldn't be equally likely to find the rote learning at American schools staid and uninspiring. Organics are popular, but it's not at all a completely widespread phenomenon in terms of practice, even in the middle class groups I know. Organics are rhetorically prized as being better, but in the next sentence, there is a lament about how they can't be bought because they are too expensive. Add to this the fluidity of labeling and regulation in the USA--i.e. the fact that much of what is labeled as apparently "natural" or even "organicesque" is just greenwashing--and it would be hard to say that it is only a class issue: many people may buy something they think is better which may have just as much of this crap on it. In other words, I would contend that the index has some independent validity that goes beyond what are fairly superficial assumptions about kids, class and eating habits. I don't think giving all kids healthy food (and enough of it) would somehow eradicate education problems, but it couldn't hurt.
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