Sean F. Reardon’s research while affiliated with Stanford University and other places

California’s K–12 funding and instructional policies for English learners have changed significantly over the past two decades. This paper uses student-level longitudinal data from 2006 to 2019 to examine the learning outcomes of successive cohorts of students who were classified as English learners in kindergarten as they progressed through California’s changing public school system. First, we find ELs grew more diverse linguistically over time. Second, we find that their third-grade achievement improved in math and English language arts and achievement gaps narrowed in both subjects. Third, we find that more recent cohorts reported slightly higher rates of English proficiency acquisition by the end of grade 5. Finally, we find that the proportion who were reclassified by grade 5 increased dramatically for the first two cohorts of our study but then remained constant for the next five years. In the most recent cohort we can observe, only 53% of students who entered kindergarten as ELs were reclassified by the end of grade 5.

U.S. public schools are racially and economically segregated. Prior research shows that the desegregation of Southern schools beginning in the 1960s led to significant benefits for Black students. Less clear, however, is whether segregation today has the same harmful effects as it did 50 years ago and through what mechanisms segregation continues to affect achievement. We estimate the effects of current-day school segregation on racial achievement gaps using 11 years of data from all U.S. public school districts. We find that racial segregation is strongly associated with the magnitude of achievement gaps in 3rd grade and the rate at which gaps grow from 3rd to 8th grade. The association of racial segregation with achievement-gap growth is completely accounted for by racial differences in school poverty. Thus, racial segregation is harmful because it concentrates minority students in high-poverty schools, which are, on average, less effective than lower-poverty schools. Exploratory analyses show that segregation-related between-school differences in teacher characteristics are associated with unequal learning rates and account for roughly 20 percent of the effect of Black–White racial differences in exposure to poverty. Further research is needed to identify mechanisms linking school segregation to achievement-gap growth.

Cross-national studies on socioeconomic status (SES) achievement gaps have focused on the size of the gap and given less attention to where in the SES distribution the achievement gap tends to be relatively large within a society, and whether this location varies across countries. We estimate the relative size of achievement gaps between students at the 50th and 10th percentiles versus the 90th and 50th percentiles of SES distribution within a society, using the Organisation for Economic Co-operation and Development (OECD) Programme for International Student Assessment (PISA) data. We find OECD countries vary in the size of the ratio of achievement gaps at lower-tail SES and upper-tail SES. Our multivariate analyses show that the ratio is positively associated with within-country patterns of economic inequality, measured by the ratio of income inequality and the ratio of segregation at lower-tail and upper-tail SES. We do not find evidence of an association between the achievement gap ratio and patterns of educational stratification.

Recent studies have shown that U.S. Census- and American Community Survey (ACS)-based estimates of income segregation are subject to upward finite sampling bias (Logan et al. 2018; Logan et al. 2020; Reardon et al. 2018). We identify two additional sources of bias that are larger and opposite in sign to finite sampling bias: measurement error-induced attenuation bias and temporal pooling bias. The combination of these three sources of bias make it unclear how income segregation has trended. We formalize the three types of bias, providing a method to correct them simultaneously using public data from the decennial census and ACS from 1990 to 2015-2019. We use these methods to produce bias-corrected estimates of income segregation in the United States from 1990 to 2019. We find that (1) segregation is on the order of 50% greater than previously believed; (2) the increase from 2000 to the 2005-2009 period was much greater than indicated by previous estimates; and (3) segregation has declined since 2005-2009. Correcting these biases requires good estimates of the reliability of self-reported income and of the year-to-year volatility in neighborhood mean incomes.

We use data from the Stanford Education Data Archive to describe district-level trends in average academic achievement between 2009 and 2019. Although on average school districts’ test scores improved very modestly (by about 0.001 standard deviations per year), there is significant variation among districts. Moreover, we find that average test score disparities between nonpoor and poor students and between White and Black students are growing; those between White and Hispanic students are shrinking. We find no evidence of achievement-equity synergies or trade-offs: Improvements in overall achievement are uncorrelated with trends in achievement disparities. Finally, we find that the strongest predictors of achievement disparity trends are the levels and trends in within-district racial and socioeconomic segregation and changes in differential access to certified teachers.

Background Cardiovascular disease (CVD) disproportionately affects Black adults in the United States. This is increasingly acknowledged to be due to inequitable distribution of health-promoting resources. One potential contributor is inequities in educational opportunities, although it is unclear what aspects of education are most salient. School racial segregation may affect cardiovascular health by increasing stress, constraining socioeconomic opportunities, and altering health behaviors. We investigated the association between school segregation and Black adults’ CVD risk. Methods and findings We leveraged a natural experiment created by quasi-random (i.e., arbitrary) timing of local court decisions since 1991 that released school districts from court-ordered desegregation. We used the Panel Study of Income Dynamics (PSID) (1991 to 2017), linked with district-level school segregation measures and desegregation court order status. The sample included 1,053 Black participants who ever resided in school districts that were under a court desegregation order in 1991. The exposure was mean school segregation during observed schooling years. Outcomes included several adult CVD risk factors and outcomes. We fitted standard ordinary least squares (OLS) multivariable linear regression models, then conducted instrumental variables (IV) analysis, using the proportion of schooling years spent in districts that had been released from court-ordered desegregation as an instrument. We adjusted for individual- and district-level preexposure confounders, birth year, and state fixed effects. In standard linear models, school segregation was associated with a lower probability of good self-rated health (−0.05 percentage points per SD of the segregation index; 95% CI: −0.08, −0.03; p < 0.001) and a higher probability of binge drinking (0.04 percentage points; 95% CI: 0.002, 0.07; p = 0.04) and heart disease (0.01 percentage points; 95% CI: 0.002, 0.15; p = 0.007). IV analyses also found that school segregation was associated with a lower probability of good self-rated health (−0.09 percentage points; 95% CI: −0.17, −0.02, p = 0.02) and a higher probability of binge drinking (0.17 percentage points; 95% CI: 0.04, 0.30, p = 0.008). For IV estimates, only binge drinking was robust to adjustments for multiple hypothesis testing. Limitations included self-reported outcomes and potential residual confounding and exposure misclassification. Conclusions School segregation exposure in childhood may have longstanding impacts on Black adults’ cardiovascular health. Future research should replicate these analyses in larger samples and explore potential mechanisms. Given the recent rise in school segregation, this study has implications for policies and programs to address racial inequities in CVD.

OBJECTIVES Few researchers have evaluated whether school racial segregation, a key manifestation of structural racism, affects child health, despite its potential impacts on school quality, social networks, and stress from discrimination. We investigated whether school racial segregation affects Black children’s health and health behaviors. METHODS We estimated the association of school segregation with child health, leveraging a natural experiment in which school districts in recent years experienced increased school segregation. School segregation was operationalized as the Black-White dissimilarity index. We used ordinary least squares models as well as quasi-experimental instrumental variables analysis, which can reduce bias from unobserved confounders. Data from the Child Development Supplement of the Panel Study of Income Dynamics (1997–2014, n = 1248 Black children) were linked with district-level school segregation measures. Multivariable regressions were adjusted for individual-, neighborhood-, and district-level covariates. We also performed subgroup analyses by child sex and age. RESULTS In instrumental variables models, a one standard deviation increase in school segregation was associated with increased behavioral problems (2.53 points on a 27-point scale; 95% CI, 0.26 to 4.80), probability of having ever drunk alcohol (0.23; 95% CI, 0.049 to 0.42), and drinking at least monthly (0.20; 95% CI, 0.053 to 0.35). School segregation was more strongly associated with drinking behaviors among girls. CONCLUSIONS School segregation was associated with worse outcomes on several measures of well-being among Black children, which may contribute to health inequities across the life span. These results highlight the need to promote school racial integration and support Black youth attending segregated schools.