This article first appeared in School Administrator.

To much of the public, it’s self-evident that public schools are “failing” when large achievement gaps separate middle-class white and low-income minority youth. Why, they ask, should skin color or family earnings affect whether children may benefit from effective teachers?

Of course, minority or low-income status does not itself depress achievement, but on average, disadvantaged children achieve at lower levels. International tests confirm this in every industrialized country.

Why is this so? Poor nutrition, inadequate health care, substandard housing and unstable families — all are factors that contribute to a child’s inability to learn at high levels.

Each of these well-documented social class differences between middle-class and low-income students has a small effect on average performance, but their cumulative effect explains much of the achievement gap.

Richard Rothstein, research associate at the Economic Policy Institute, is one of the nation’s authorities on the impact of socioeconomic factors on disparities in student achievement.

Isolation’s Impact

The negative effects of racial and economic disadvantage are exacerbated when low-income black students are concentrated in segregated schools. Remediation becomes routine, and teachers must focus more on discipline and less on instruction, leaving them little time to challenge those exceptional students who can overcome personal, family and community hardships that typically interfere with learning.

This isolation is a problem not only of poverty but of race. In urban areas, low-income white students are more likely integrated into middle-class neighborhoods and less likely to attend schools filled with other disadvantaged students. Nationwide, low-income black students’ isolation has increased. The share of black students attending schools that are less than 10 percent white increased from less than 34 percent in 1989 to 39 percent in 2007. In 1989, black students typically attended schools where 43 percent of students were low-income; by 2007, this grew to 59 percent. (Statistics provided by a 2009 report by the Civil Rights Project at UCLA, http://civilrightsproject.ucla.edu.)

Schools with poorly performing students cannot be turned around while they remain racially and socioeconomically isolated. The problems these students bring to school are so overwhelming that policy should never assume that even the most skilled faculty can overcome them. Schools certainly can make a difference, but they cannot fully erase damage caused by concentrated poverty and racial isolation.

Regulated Housing

Throughout most of the 20th century, federal policy created black ghettos in metropolitan areas by placing public housing for white and black families in separate neighborhoods; guaranteeing low-cost mortgages for white (but not black) families to move from this public housing and from other urban neighborhoods to all-white suburbs of single-family homes; establishing bank and savings and loan regulatory policies that included racial discrimination as part of sound lending policy; granting tax exemptions to organizations formed for the purpose of enforcing racial barriers and to other organizations (and churches) for whom this was also a purpose; and deliberately routing federal highways through cities to create racial barriers and segregation.

State governments heavily regulated a real estate industry that sold and rented homes to whites in neighborhoods designated for whites, and (if at all) to blacks in neighborhoods designated for blacks. State prosecutors and local police tolerated, even encouraged, mob violence against African Americans who dared try to move into white-only neighborhoods.

High Court Ruling

Sociological, economic and historical research demonstrates that black student performance improves with integration, without any loss for whites. However, in 2007, the U.S. Supreme Court, in its Parents Involved in Community Schools v. Seattle School District No. 1 ruling, prohibited districts from taking race into account when assigning pupils to schools in an attempt to integrate. The decision arose from cases in Seattle, Wash., and Louisville, Ky., where the school districts used race as a factor to achieve diversity when assigning students to schools.

Expressing the plurality opinion, Chief Justice John Roberts asserted that explicit racial integration was permissible only to remedy a previous explicit policy of segregation. He said that black students’ isolation today is not deliberate; rather, it results from de facto neighborhood segregation that arose from income differences, demographic trends, and choices of white and black families to live in same-race neighborhoods. The dissent, by liberal Justice Stephen Breyer, did not disagree on this point, arguing only that for de facto segregation, it is good public policy to permit districts voluntarily to integrate, even if not constitutionally compelled to do so.

But segregation in Seattle and Louisville was no accident. It was created largely by public policy. In Seattle, subdivisions created by mega-builders (such as William Boeing) were financed by the federal government with racial restrictions, or designated for whites-only in plans approved by the city and county. In Louisville, when a pro-integration couple sold a home in their white neighborhood to a black purchaser, not only did police stand by during the ensuing riot, but prosecutors responded by trying, convicting and imprisoning the white seller for “sedition.”

Forgotten Practices

Both Roberts’ and Breyer’s opinions reflect colossal historical amnesia. In truth, neighborhoods across the nation in which our schools are located were segregated by purposeful federal, state and local government policy. Many such policies are no longer in force, but their effects endure.

In 1954, the Supreme Court, in Brown v. Board of Education, prohibited school districts from maintaining separate schools for blacks and whites. The decision was aimed at practices in the South and assumed that blacks and whites lived in the same neighborhoods and could attend the same schools if permitted to do so. But the Brown decision could do little to remedy segregation that results not from a racial pupil assignment plan but from geographic separation of the races. Busing is rarely a solution because distances between affluent white suburbs and urban black ghettos are now too great in many ­metropolitan areas.

Simply repealing the kind of school segregation policy banned by the Brown decision can integrate schools if districts draw integrated school attendance zones. But repealing an intentional residential segregation policy that already has led to substantial racial isolation accomplishes little, because once populations have been firmly established in separate areas, even modest integration could take decades if left to ordinary vacancies and in-migration.

Consider the iconic Levittown suburb in Nassau County, N.Y. In 1947, a vast housing shortage existed for both black and white workers and returning war veterans. The federal government financed the Levitt company to construct 17,000 units. These Levittown homes were easily affordable, but the government explicitly prohibited Levitt from selling (or renting) to African Americans. (Similar federal restrictions applied to other projects, many obscure and some well known, like the giant Lakewood development south of Los Angeles and the Daly City suburb south of San Francisco, memorialized by Malvina Reynolds’ song about “ticky tacky” houses.)

An executive order by President Kennedy in 1962 and the 1968 Fair Housing Act repealed government policies requiring racial housing segregation. Yet although many black families in New York City and Nassau County need better housing, Levittown remains today less than 1 percent black, compared to the nearby Long Island town of Roosevelt, which is 79 percent black.

In part, this is because white families fortunate enough to purchase Levittown homes in the 1940s and ’50s saw their equity appreciate more rapidly than their wages, so asset values helped propel them into the middle class. But by the time legal barriers to segregation fell, these homes were no longer affordable for working families, so African Americans were permanently excluded from the suburban boom and its amenities.

A Myth Perpetuated

That our segregation is de facto, not de jure (created by law and public policy) is an urban myth, shared by Supreme Court justices, national policymakers, legislators and educators. We continue to teach this myth in public schools, where social studies curricula characterize residential racial segregation as resulting only from private discrimination or as a purely random phenomenon.

For example, in the more than 1,200 pages of McDougal Littell’s widely used high school textbook, The Americans, a single paragraph is devoted to “Discrimination in the North” in the 20th century. The book devotes one sentence to residential segregation: “African Americans found themselves forced into segregated neighborhoods,” with no further explanation of how this happened or who was responsible. Similar cover-ups characterize the textbooks of other publishers.

Superintendents cannot hope to narrow the achievement gap without integrating their student populations, and they cannot hope to do this until the neighborhoods from which students come are integrated. Although federal, state and local governments have many policy alternatives they could employ to promote residential integration, there is no popular support for such policies.

This lack of public support is partly our own fault, because we fail to teach an accurate account of the segregation policies that were the most important determinant of our contemporary metropolitan landscape. As a result, the myth of de facto segregation endures. If we don’t teach students that residential segregation was unconstitutionally created by our government, and requires a constitutional remedy, how can we expect them, as adults, to act on this understanding?

Richard Rothstein is a research associate at the Economic Policy Institute in Washington, D.C., and author of several books, including Class and Schools: Using Social, Economic, and Educational Reform to Close the Black-White Achievement Gap (Economic Policy Institute, 2004). E-mail: rrothstein@epi.org