School segregation at multiple geographic levels : implications for educational policy
Keywords: Education.

Segregation by race and class has been a foundational feature of U.S. society, and public education is not an exception. However, scholarly discussions have often missed geographic layers in the phenomenon of school segregation and its relevance to the decentralized U.S. education system, in which state and district governments operate as additional political divisions to the federal government. This dissertation consists of three papers investigating the patterns and consequences of, as well as remedies for, segregation across schools and neighborhoods at various geographic levels. The first paper documents trends in racial economic segregation among U.S. public schools during the last three decades and decomposes these trends into different geographic scales (e.g., between-state, between-district, and within-district segregation). It focuses on racial differences in exposure to school poverty, a dimension of school segregation that has faced less academic scrutiny despite its substantive importance as the strongest predictor of racial achievement gaps. The results of this study show that racial economic segregation has decreased since the late 1990s, yet Black students are still considerably isolated in schools with higher poverty rates. Between-district segregation has been the largest component of racial economic segregation, whereas within-district segregation has steadily grown during the last three decades. These findings suggest the imperativeness of inter-district policy remedies while also highlighting intra-district policy needs for promoting student diversity across schools in the district. The second paper examines state-level socioeconomic achievement gaps and their association with between-district income segregation. Socioeconomic achievement gaps have long been a central focus of educational research. However, not much is known about how (and why) between-district gaps vary among states, even though states are a primary organizational level in the decentralized education system in the United States. Using data from the Stanford Education Data Archive (SEDA), this paper describes state-level socioeconomic achievement gradients and their growth from grades 3 to 8. It also examines state-level correlates of the gradients and their growth, including school system funding equity, preschool enrollment patterns, the distribution of teachers, income inequality, and economic segregation. Findings show that socioeconomic gradients and their growth rates vary considerably among states and that between-district income segregation is positively associated with the socioeconomic achievement gradient. The third paper simulates intra-district desegregation policy options that focus on different dimensions of student disadvantage: race, income, and the joint condition of race and income. Student assignment policy (SAP) has emphasized within-district local control and the use of students' socioeconomic status rather than race since the 1990s. Although prior research on SAP has examined how a new generation of SAP affects school segregation, none of these studies investigate how it impacts racial economic segregation, the strongest predictor of racial achievement gaps. Moreover, none of the prior studies scrutinize how the race- and income-based SAP contribute to desegregation differently, even though the distinction between these two strategies has been an ongoing legal question since the Seattle School District No.1 case in 2007. This study simulates three different within-district student assignment strategies, each of which focuses on student race, income, and the joint condition of race and income. Findings from this study show that the race- and income-based strategies reduce racial economic segregation across schools at a similar pace, although the income-based strategy is slightly less efficient. The inefficiency of the income-based strategy compared to the race-based one becomes more pronounced if aiming for a larger reduction in school segregation. As expected, the race-and-income-based strategy most efficiently decreases racial economic segregation. Moreover, the relative efficiency of the race-based strategy is more salient among districts with higher school poverty rates and racial economic segregation