The Intersection

SES Inequality in the U.S.: A Between-School or Within-School Issue?

November 18, 2015


For years now, the focus of U.S. education policy has been about the problem of “failing schools.” Whether the specific proposal under discussion involves charter schools, school finance, principal leadership, school size, or what have you, the underlying assumption is the same: improving the performance of low-achieving schools is the key to addressing educational equality and excellence.

However, new research suggests that a single-minded emphasis on differences in achievement between schools may be blinding us to the problem of differences occurring within schools. In an article published in the latest Education Researcher – which I authored with Nathan Burroughs, Pablo Zoido, and Richard Houang – data was analyzed from the 2012 Program for International Student Assessment (PISA) study, concluding that most of the variation in student performance on mathematics literacy lies not between schools, but within them.

This finding holds not just for the United States, but also for a majority of more than 60 countries that participated in the PISA. As it turns out, the Unites States stands out for having greater-than-average gaps in performance between students from richer and poorer backgrounds within the same school. One of the chief contributors to this problem is unequal exposure to rigorous mathematics content. Building on previous work, we (Schmidt et al.) provide strong evidence that exposure to mathematics content – also known as “opportunity to learn” (OTL), has a powerful influence on student learning. Unfortunately, we concluded that in every country, including the United States, students from disadvantaged backgrounds are systematically exposed to weaker OTL with dramatic long-term consequences.

Despite the public abandonment of the system of tracking – placing disadvantaged students in classrooms with weaker instructional content – the PISA suggests that these curricular inequalities are still very widespread. Our analysis indicates that the United States exhibits particularly large within-school inequalities in OTL as well as one of the strongest within-school relationships between a student’s family background (measured by an index of socioeconomic status) and exposure to mathematics content. This is related to the fact that the United States has one of the largest within-school achievement gaps on PISA.

None of this is to say that between-school differences aren’t important, or that policymakers and researchers shouldn’t devote attention to addressing the problem of “failing schools.” However, our work implies that focusing exclusively on low-performing schools cannot guarantee more equal educational opportunities for American children. The data indicate that nearly 90 percent of the variation in opportunity to learn rigorous mathematics exists within the same schools – not between them. This finding buttresses earlier work that students in different classrooms might be using the same textbooks and same course titles, yet experience profoundly different instructional content. Therefore, the challenge of closing achievement gaps requires much more concentrated effort on ensuring that every student in every classroom in a given grade receives the same opportunity to learn challenging mathematics – a mission of vital importance in today’s increasingly technological world.

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