poverty and intelligence: there is a correlation.
I am considering creating an "Um...duh" article category. A study by the University of Berkley found that there is a strong correlation between poverty and brain functioning, with the study demonstrating that the cognitive abilities of low-income 9 & 10 year olds pale in comparison to those of their wealthy counterparts. When their cognitive abilities were tested, the former demonstrated that they had drastically less attention for cognitive testing, lead researcher Mark Kishiyama of the University of California-Berkeley explains: "It suggests that in these kids, prefrontal function is reduced or disrupted in some way."
Now, correlation does not necessarily mean cause. That is, it isn't the fact of living in a family that has little wealth that leads to a narrowing ability to use one's brains. However, many social aspects accompanying poverty affect brain functioning: poor and discouraging education, unavailable parents or guardians, malnutrition, poor health insurance, exposure to lead, lack of mentally stimulating resources like museums and pretty libraries, and being told by society that poor people are uneducated, trashy, and that they arrived in their social situation because they are inherently destined to be so. Take a long walk through Brooklyn from East New York to Bed-stuy to Fort Green to Prospect Heights to Park Slope. You'll get the drift.
Primary education across the US, is supposed to be, at least on paper, the right of all citizens of the US. However, because taxes which go to public school education is not centralized but localized, young people who have the privilege of having parents who can pay higher taxes also have the privilege of attending schools with books and tutors and computers and ceilings without holes in them. Now, money doesn't guarantee success, and there are ideological factors. For example, because the wealthy are financially privileged and likely white no one is overtly surprised when they do well in school or overtly disappointed when they fail - unlike their impoverished and likely colored counterparts who find success to be coincidential and failure to be characteristic of "who they are."
Now, contrast all that with those wonderful banking families who are using the interest from your college loans to buy their kids ponies.