This idea is captured by this excerpt:
To make this trend concrete, consider two children, one from a family with income of $165,000 and one from a family with income of $15,000. These incomes are at the 90th and 10th percentiles of the income distribution nationally, meaning that 10 percent of children today grow up in families with incomes below $15,000 and 10 percent grow up in families with incomes above $165,000.
In the 1980s, on an 800-point SAT-type test scale, the average difference in test scores between two such children would have been about 90 points; today it is 125 points. This is almost twice as large as the 70-point test score gap between white and black children. Family income is now a better predictor of children’s success in school than race.And a key point to remember is that the disparity between rich kids and poor kids is widening while racial/ethnic disparities have been slowly decreasing.
The widening income disparity in academic achievement is not a result of widening racial gaps in achievement, either. The achievement gaps between blacks and whites, and Hispanic and non-Hispanic whites have been narrowing slowly over the last two decades, trends that actually keep the yawning gap between higher- and lower-income students from getting even wider. If we look at the test scores of white students only, we find the same growing gap between high- and low-income children as we see in the population as a whole.Professor Reardon explains the implications of this phenomenon on our society:
Meanwhile, not only are the children of the rich doing better in school than even the children of the middle class, but the changing economy means that school success is increasingly necessary to future economic success, a worrisome mutual reinforcement of trends that is making our society more socially and economically immobile.The entire piece is well worth reading. Check it out!