The blog of the Urban Institute
September 22, 2021

School Boundaries Can Cause Unnecessary Segregation: A Case Study in Illinois

September 22, 2021

More than 65 years after the landmark Brown v. Board of Education case, racial segregation in American schools remains pervasive and may be worsening (PDF). Using neighborhood and school enrollment demographic data, my colleagues and I developed a set of criteria to determine which school or district boundaries result in the most racial segregation. But there’s also a legal test of segregation established in the 1974 Equal Educational Opportunities Act (EEOA), which states that if school borders within a district create a greater degree of racial segregation than would occur if students were assigned to the school closest to their residence, that district would be engaging in unlawful segregation.   

“no State shall deny equal educational opportunity to an individual on account of his or her race, color, sex, or national origin, by… the assignment by an educational agency of a student to a school, other than the one closest to his or her place of residence within the school district in which he or she resides, if the assignment results in a greater degree of segregation of students on the basis of race, color, sex, or national origin among the schools of such agency that would result if such student were assigned to the school closest to his or her place of residence within the school district of such agency providing the appropriate grade level and type of education for such student”

-Equal Educational Opportunities Act 

Many students are zoned to a school that is not geographically closest to their home. This might be because the closest school is in a different school district or locality than their home, or physical barriers, such as a highway, make access difficult. Often, school boundary lines align with residential segregation previously enforced by redlining or restrictive covenants. But if school boundaries are increasing segregation, the district could be in violation of federal law and obligated to redraw its boundary lines. 

Consider Illinois, which is the most racially representative state in the US. Among the 126 Illinois school boundary pairs we identified as highly segregated—that is, places where there is a substantial demographic difference between students on either side of the school or district line—there is an average 36.8 percentage point difference between the combined Black and Hispanic populations across the two schools. This means schools with shared boundaries, one might have a Black and Hispanic population share of 60 percent, while the other is only 23 percent. But given the presence of residential segregation, would assigning students to the school nearest to their home result in more integrated school pairs?

To test this, we gathered Illinois census-block population data by race and ethnicity for people ages 5–17 and matched each block to the school it is geographically closest to (assuming a direct path), and to the elementary school that it is zoned to. Census-block demographics differ from actual school enrollment numbers and undercount Black and Hispanic populations in our case study schools, but these data are useful for broadly identifying patterns of racial segregation.

If every student went to the school nearest their home, these segregated school pairs would have an average 35.3 percentage point difference between the combined Black and Hispanic populations. Additionally, 63 percent (80 of 126) of the school pairs we identified are more segregated across boundary lines than they would be if every student went to their nearest school.

Take these two bordering school zones located in the same district in the Urbana-Champaign metropolitan region. These schools have a large racial disparity despite being only a five-minute drive apart and serving the same grade levels. The left shows the actual school attendance boundaries by census block, and the right is a hypothetical attendance region that assumes every student attends their nearest school.

Two maps of two schools and their attendance boundaries in Illinois, with the map on the left showing the schools’ current boundaries and the map on the right showing hypothetical boundaries where every student attends their nearest school.

The boundaries for these schools were likely designed around main streets or highways, and the boundaries for school B might relate to the residential areas surrounding a major university campus contained in the borders. The area to the east of the university, which is majority white and Asian, is incorporated into school B while the neighborhood to the west, which is more integrated, is zoned to a third school. A neighborhood to the north of the university, which is majority Black, is also left out of the boundary. If every student were zoned to their nearest school, some students from these neighborhoods to the west and north would attend school B, and school A’s borders would expand to encompass much of the surrounding, less dense areas that are majority white.

Under the nearest school scenario, the difference between the share of Black and Hispanic students across the two schools decreases from 37 to 21 percentage points. This result suggests these schools might meet the threshold for unlawful segregation outlined in the EEOA. Though there is still a sizeable demographic discrepancy, this exercise demonstrates that school boundary decisions can artificially segregate students into schools less diverse than their neighborhoods.

A vertical bar chart comparing the share of Black or Hispanic students in two schools under their actual school boundary composition with the share of Black or Hispanic students in a hypothetical boundary composition where they attend their nearest school

There are several caveats, however. The geographically nearest school assignment doesn’t take into account school capacity limits or actual transportation times, which are affected by the availability of public transit and street design (factors often rooted in structural racism). The nearest-school scenario encompasses significantly more students than the actual school boundaries in our example, and the inverse is true in other pairs. Additionally, the census data encompass everyone between ages 5 and 17, a larger range than elementary schools enroll. Further, unlike in the example, the majority of the segregated boundary pairs we identified are located in different school districts, while the EEOA relates only to schools within a single district.

These are all important considerations, but they have too often been used to justify inaction. Though the exact assignments created in this hypothetical are flawed, the borders between these two schools and many others can certainly be redrawn to reduce inequity. The urgency of racial integration in our schools is clear, as are the benefits to all students.

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(Jose Luis Pelaez Inc/Getty Images)


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