Poverty and performance, updated

Diane Ravitch has been a supporter of both school-choice and standards. In a recent article in the Wall Street Journal, she seems to take back her support for both. This is interesting and worthy of discussion of itself, but I thought the most interesting part came in the third-to-last paragraph (emphasis mine).

The current emphasis on accountability has created a punitive atmosphere in the schools. The Obama administration seems to think that schools will improve if we fire teachers and close schools. They do not recognize that schools are often the anchor of their communities, representing values, traditions and ideals that have persevered across decades. They also fail to recognize that the best predictor of low academic performance is poverty—not bad teachers.

I know this isn't the main point of her article, but I can't help wondering, does anybody really believe this? I mean, I know we're all supposed to pretend that being poor makes you dull, but isn't the other way around at least as as likely? The irony is that speaking the plain truth, that some kids are not smart enough to meet tough standards, makes her argument against those standards even stronger. Unfortunately, it bumps up against the Immovable Object, the fantasy that we are each born perfect, capable of anything, until our parents and society and I-don't-know-what-all make us flunk out of eighth grade.

Until we're ready to start talking like adults we have absolutely no hope of improving anything.

Update:
The graph below was scanned (probably illegally - sorry) from Charles Murray's The Bell Curve. It shows the effects of socio-economic status (SES) and IQ on one measure of school performance, namely getting a degree.

The graph clearly shows that IQ is a much better predictor than SES is of at least this particular measure of performance. Look at it this way: if somebody said to you, Tell me whether Joe Blow here ever got his diploma. I'll give you one piece of information about him, you would ask whether he was smart, not whether he was poor. In other words, IQ is a better predictor than poverty.