But rising income inequality explains, at best, half of the increase in the rich-poor academic achievement gap. It’s not just that the rich have more… - Sean Reardon

Before we can figure out what’s happening here, let’s dispel a few myths. The income gap in is not growing because the test scores of poor students are dropping or because our schools are in decline. [...] 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.

It might also mean greater business and government support for maternity and paternity leave and day care so that the middle class and the poor can get some of the educational benefits that the early academic intervention of the rich provides their children. Fundamentally, it means rethinking our still-persistent notion that educational problems should be solved by schools alone. The more we do to ensure that all children have similar cognitively stimulating early childhood experiences, the less we will have to worry about failing schools. This in turn will enable us to let our schools focus on teaching the skills — how to solve complex problems, how to think critically and how to collaborate — essential to a growing economy and a lively democracy.

If not the usual suspects, what’s going on? It boils down to this: The academic gap is widening because rich students are increasingly entering kindergarten much better prepared to succeed in school than middle-class students. This difference in preparation persists through elementary and high school. As you may have heard, the incomes of the rich have grown faster over the last 30 years than the incomes of the middle class and the poor. Money helps families provide cognitively stimulating experiences for their young children because it provides more stable home environments, more time for parents to read to their children, access to higher-quality child care and preschool and — in places like New York City, where 4-year-old children take tests to determine entry into gifted and talented programs — access to preschool test preparation tutors or the time to serve as tutors themselves.