In a front page Washington Post story today, reporter Alec MacGillis questions former Democratic Senator John Edwards’s signature idea for alleviating poverty: reducing economic segregation. Edwards argues, “if we truly believe that we are all equal, then we should live together too,” and proposes providing 1 million rental housing vouchers that the poor could use to live in more affluent neighborhoods.

MacGillis attacks this plan, saying: “The idea sounds bold, but it faces a deflating reality: A major federal experiment conducted for more than a decade has found that dispersing poor families with vouchers does not improve earnings or school performance, leaving some economists puzzled that Edwards would make such dispersal a centerpiece of his anti-poverty program.” Then comes the “gotcha”: “Edwards said he was unaware of the experiment.”

In fact, however, dozens of studies going back forty years have indicated that giving poor kids a chance to attend middle-class schools is probably the single most effective policy option available for raising their achievement levels and life chances. The seminal 1966 Coleman Report found that the most important predictor of academic achievement, after the socioeconomic status of the family a child comes from, is the socioeconomic makeup of the school she attends—a finding replicated in an enormous number of studies since then. While it is possible to make schools with high concentrations of poverty work—we all know of such individual schools—it is extremely uncommon. A study by University of Wisconsin professor Douglas Harris, for example, found that middle-class schools (those with fewer than 50 percent of students eligible for free and reduced-price lunch) are twenty-two times as likely to be consistently high performing as high-poverty schools (those with 50 percent or more of students eligible for subsidized lunch).

Middle-class schools perform better in part because middle-class students on average receive more support at home and come to school better prepared. But the vastly different educational environments typically found in middle-class and high-poverty schools also have a profound effect on achievement. On the 2005 National Assessment of Educational Progress (NAEP) given to fourth graders in math, for example, low-income students attending more affluent scored substantially higher (239) than low-income students in high poverty schools with 75 percent or more low income (219). This twenty-point difference is the equivalent of almost two year’s learning. Indeed, low-income students given a chance to attend more affluent schools performed more than half a year better, on average, than middle-income students who attend high-poverty schools (231). At the high school level, similar results are found. In 2005, for example, University of California professor Russell Rumberger and his colleague Gregory J. Palardy found that a school’s socioeconomic status had as much impact on the achievement growth of high school students as a student’s individual economic status.

Likewise, a Chicago program to provide low-income minority residents a chance to move to more affluent suburbs found that their children did much better than those who wished to participate in the program but were left behind because of insufficient space. Northwestern University researchers found that the children of suburban moves were four times more likely to finish high school than city movers and were almost twice as likely to attend college.

Attending a more affluent school matters because virtually everything that educators talk about as desirable in a school—high standards and expectations, good teachers, active parents, a safe and orderly environment, a stable student and teacher population—are more likely to be found in economically mixed schools than in high poverty schools.

So why did the study that MacGillis cites—an evaluation of the federal Moving to Opportunity program—come up with such unimpressive results, with no real gains for students? Upon close examination, there were major flaws in the structure of the program, which meant that most poor families didn’t move to opportunity but in essence, moved to mediocrity. Students in the opportunity program attended schools with a free and reduced price lunch mean of 67.5 percent, compared to 73.9 percent in the control group. And students in the experiment attended schools with an average achievement at the nineteenth percentile, compared to the fifteenth percentile for the control group. Clearly, this was not a fair test of whether genuine poverty deconcentration can affect the achievement of students.

The Moving to Opportunity results suggest that housing voucher programs need to ensure that opportunities are truly open, so that low-income families are not simply moving from horrible neighborhoods to bad ones. And housing programs can be supplemented by education programs to ensure that low-income students, whatever their neighborhood, have access to middle-class schools. In Wake County, North Carolina, where John Edwards sent his older children to the public schools, officials have created an innovative plan using magnet schools and other means to give all children a chance to attend good, middle-class schools. In 2000, the school board set a policy goal that no school should have more than 40 percent of students eligible for free or reduced price lunch. The results are impressive: low-income Wake County students do much better than low-income students in other big North Carolina districts that don’t have programs to alleviate poverty concentrations. On the 2005 High School End of Course exams, 63.7 percent of low-income students in Wake County passed, compared to 48.7 percent in Durham County, 47.8 percent in Guilford County, and 47.8 percent in Mecklenburg County. Likewise, 82.2 percent of Wake County’s students graduated on time from high school in 2002–03—the second highest rate among the nation’s largest fifty districts nationally. By comparison, 66.2 percent of students in North Carolina and 69.6 percent nationally graduated on time.

At long last, a politician has offered a promising alternative to the usual small-bore education reforms for poor kids. Too bad the Washington Post missed the significance of his proposals.

Richard D. Kahlenberg is a Senior Fellow at The Century Foundation.