The link between children's academic achievement and family income

Sociologist Sean Reardon discusses the academic achievement gap between the rich and the poor in America.

Meeri Kim: Your research looks at the causes, patterns, trends, and consequences of social and educational inequality. Could you describe your findings on the income-achievement gap in the U.S.? Why does such a gap exist?

Sean Reardon: We’ve looked back at data over the last 50 years of test scores of children from kindergarten through 12th grade, and, in particular, at the achievement gap between children from high- and low-income families. As income inequality has grown in the U.S. over the last few decades, the income achievement gap has also grown; this gap was about 40% larger among children born in the 1990s than among those born in the 1970s.

So where does this widening gap come from? It isn’t because low-income kids’ test scores have gone down — actually test scores have gone up for both low- and high-income kids over time. But the test scores of children from high-income families have increased more rapidly than those from low-income families, and particularly the test score gap between the affluent and middle class has widened significantly. We think that this is due to two main factors: widening income inequality and an increased investment in kids’ cognitive development by affluent families.

“Most of the disparity is already there from when kids enter kindergarten.”

MK: At what age do you see this achievement gap start to happen, and does it get worse as children get older?

SR: The achievement gap is actually evident in the earliest data that we have. If we look at test score data on school readiness from kids entering kindergarten — basic literacy, pre-literacy skills, and pre-numeracy skills — the gap between high- and low-income kids is already large and does not grow significantly as they progress through school. The gap does grow a little bit from kindergarten to eighth grade and high school, but only by about 10 to 20%. Most of the disparity is already there from when kids enter kindergarten.

MK: Some experts believe educational achievement is analogous to innovations in public health, where a new drug starts by being accessible only to high-income patients and later spreads to the masses. Do you believe that the achievement gap can be alleviated through greater knowledge dissemination and access?

SR:  It’s one plausible hypothesis. For example, when we look at the most recent years of data —kids who entered kindergarten in 1998 compared to those who entered in 2010 — the school readiness gap narrowed by about 15% during that period. Before that, the achievement gap had been widening for two decades. It still isn’t as small as it was 40 years ago, but it has gotten a little bit smaller than it was.

Part of the reason we think the gap grew initially is that high-income families were investing a lot into their kids’ cognitive development, particularly in early childhood. Examples of investment and enrichment activities include paying for high-quality childcare, preschool, reading to their kids a lot, and exposing them to cognitively stimulating activities.

“There’s evidence that those kinds of behaviors have diffused more broadly across the income distribution lately.”

There’s evidence that those kinds of behaviors have now diffused more broadly across the income distribution lately. We see more low-income families reporting that they’re reading to their kids, taking their kids to museums, libraries, and zoos, and their kids are playing more learning games on computers in early childhood.

While all of those things have increased for everyone, they’ve actually increased a lot more in the last decade or so for low-income families, which suggests some sort of diffusion of these kinds of investment and enrichment activities.

MK: Do you believe that public policy enforcing universal basic income would have a positive impact on the achievement gap in the U.S.?

“Money doesn’t change – or at least won’t quickly change – parents’ human capital, their social networks, or their access to other kinds of resources.”

SR: Certainly, one key thing that distinguishes the poor from the middle class is that the poor have less money. If you want to help the poor, one obvious approach is basic income support. But the real question remains: Is changing income enough?

It’s likely that basic income will help because the poor will have less stress, more financial stability, and access to better housing or neighborhoods. However, money doesn’t change – or at least won’t quickly change – parents’ human capital, their social networks, or their access to other kinds of resources.

“Because achievement gaps are self-perpetuating, the earlier we intervene to reduce them, the more effective we will be at eliminating them in the long run.”

MK: What can schools or education policymakers do to help reduce the income-achievement gap?

SR: Schools have a key role to play in the efforts to reduce this gap. First, states and school districts could devote a greater share of their resources and efforts to the earliest grades, including kindergarten and preschool. Because achievement gaps are self-perpetuating, the earlier we intervene to reduce them, the more effective we will be at eliminating them in the long run.

States and school districts can also do more to ensure that all students have equal access to high-quality teachers, stimulating curriculum and instruction, and adequate school resources.