Some schools have more resources and offer students better opportunities than others. That’s true even within a given school district. The lines on a map that determine which students go to which school are called attendance zone boundaries (AZBs).

These boundaries are redrawn frequently, typically in response to imbalances in population growth among existing school populations. Differences in quality and student opportunity from school to school mean these changes are consequential policy decisions. Changing schools can have a significant impact on a student’s educational outcomes.

Attendance Zone Boundaries and Racial Segregation

Before Brown v. Board of Education determined the practice to be unconstitutional, some school districts used AZBs to assign children of different races to separate schools. Even after that landmark case, these boundaries continue to contribute to the segregation of students in some places around the country.

Just as attendance zone boundaries can segregate schools by race, they are also a powerful tool that educational leaders can use to disrupt patterns of inequity.

People with more resources—disproportionately white—often choose where to live based in part on their perception of the quality of the local schools. Even people without school-aged children consider these boundaries, as perceptions of school quality directly affect home values. (In fact, one of the most common places to find data on attendance zone boundaries is on real estate websites.)

The same relatively affluent people also often advocate for—or against, as families typically don’t see boundary changes as desirable—AZB changes for the same reasons. This “opportunity hoarding” behavior sustains effects similar to those of the legal segregation of the past, but in a different form.

Meanwhile, people with less money and power–disproportionately people of color–are less likely to have the luxury of making such choices or to effectively advocate for or against boundaries changes that may affect their own children and communities.

But just as AZBs can segregate schools by race, they are also a powerful tool that educational leaders can use to disrupt patterns of inequity. And because AZB changes are generally made frequently and locally, community members may have a greater opportunity to influence them than they do many other decisions that affect their lives.

What the D.C. Data Says

For my dissertation at Pennsylvania State University, I looked at AZB changes in the 24 school districts in the Washington, D.C., metro area, from 2000 to 2020 (this paper presents some of the findings). Many of these districts are quite large—the largest one has 139 zoned elementary schools and the average district in this sample has 32—meaning AZBs do a lot of work sorting students. I wanted to see how redrawing boundaries affects children of different races—including in terms of travel time to school and access to educational opportunity.

The role of these boundaries is understudied, and just collecting the relevant data was a challenge. While maps of current AZBs are generally available for a given district, information on what boundaries looked like in the past can be hard to find. However, with the help of historical maps and other data sources, I was able to make a few evidence-based findings:

Black and Hispanic children are most affected

In the 2000s, 28 percent of Black children were affected by rezoning, compared to 16 percent of Hispanic children, 14 percent of white children, and 12 percent of Asian children. While rezoning was somewhat less common in the 2010s, the same general patterns persisted.

AZB changes reinforce and deepen inequality of opportunity

For example, compared to white and Asian children, Black and Hispanic children are rezoned to schools with lower proportions of experienced teachers and lower math and reading proficiency rates. This is true even when accounting for the opportunity available a child’s previous school.

Unequal zoning changes are moving outward in the D.C. metro area

Between 2010-2020, some of the most unequal changes occurred in outer-ring suburban school districts. These are places where populations are growing rapidly and racially diversifying.

What Schools–and Communities–Should Do

So what can educational leaders and members of school communities do to work toward equitable AZBs? Some argue that we should focus on improving the quality of all schools. Of course, we should work to improve all schools. But that’s not enough. We also need to make sure all children have access to equitable, diverse schools.

When redrawing AZBs, educational leaders should consider making racially diverse schools an explicit goal, alongside other goals they may have. They can position rezoning as an exciting opportunity to help dismantle inequalities and create more equitable schools in their district.

Educational leaders and community members must also resist arguments, often made against AZB changes, that increase inequality. Oftentimes these arguments use language that avoids explicit mention of race or racialized impacts (sometimes called “race-evasive” language). To counter this increasing trend, communities should engage in honest discussions of racial equity when redrawing AZBs. This is especially important in places where populations of color are just moving in and where race is becoming more salient.

Finally, educational leaders should empower communities to understand and influence the process of determining AZBs by making more data available to the public. This might include historical AZB maps, which can help communities understand how school boundaries have shaped their current context, and detailed proposals for new AZBs, which can highlight how future changes might affect different groups of students. Families and other community members should be able to easily access information about decisions that affect students.