is a senior fellow at The Century Foundation and the author of AllTogether Now: Creating Middle-Class Schools through Public SchoolChoice. This article is adapted from a Century Foundation ideabrief, "A New Way on School Integration."

For decades, conservatives have been waiting for the moment when theSupreme Court would act decisively to curtail the use of race ineducation. With Justice Samuel Alito having replaced Sandra DayO'Connor, that moment may finally have arrived.

This week, the Court heard arguments in a pair of cases pittingwhite parents against school districts in Seattle, Washington, andLouisville, Kentucky, which use race as a factor in determiningwhich schools children attend. The parents claim that this violatesthe proposition in Brown v. Board of Education that students shouldnot be treated differently because of skin color. Advocates of theschool policies, including civil rights groups, say that, underBrown, schools have a right to consider race because integrationimproves academic achievement and fosters better relations betweenraces. In Grutter v. Bollinger (2003), the Court upheld the use ofrace to promote diversity in higher education; but conservativesbelieve that, with Alito as a potential fifth vote, it may reversecourse. This would affect hundreds of school districts thatcurrently have racial integration plans similar to those of Seattleand Louisville and may also have implications for affirmativeaction at selective colleges and universities.

If the Court decides that schools can no longer take race intoconsideration, those who care about social justice will need tofind another way to promote equal educational opportunity. Luckily,roughly 40 school districts have been trying a newapproach--income-based school integration. Because of the overlapbetween race and economic status, this policy produces a healthyamount of racial diversity. At the same time, even opponents ofusing race in student assignment concede that using socioeconomicstatus is perfectly legal. Moreover, socioeconomic integrationprovides an even more powerful lever for raising achievement.

Wake County, North Carolina, which encompasses Raleigh, is a largeand growing district with a diverse population. In the early '80s,Wake County voluntarily integrated its schools by race, largelythrough a system of magnet schools. But, by the late '90s, withpressure to raise achievement and to avoid legal challenges to theuse of race, Wake officials began talking about trying somethingdifferent.

Even for liberals, the system of integrating students by race hashad its drawbacks. For one thing, it can appear to insultinglyimply that black students need to sit next to whites to learn orthat "too many" black kids make for a bad learning environment. Foranother, it hasn't always improved black achievement. Under racialdesegregation plans, for example, black student scores rose inCharlotte, North Carolina, but not in Boston, Massachusetts. Butdiscrepancies like these reveal a clue as to what does work. Thedifference between Charlotte and Boston is that in Charlotte, poorblacks had a chance to go to school with middle-class whites;whereas in Boston, poor blacks were mixed with poor whites. Theanswer isn't race--it's class.

Studies going back 40 years have found that the socioeconomic statusof the school a child attends is, after family economic status, themost powerful predictor of academic achievement. Indeed, thepositive influence of having a middle-class school environment isthe central reason why racial desegregation often improves blackachievement. As Harvard Professor Gary Orfield notes, "Educationalresearch suggests that the basic damage inflicted by segregatededucation comes not from racial concentration but from theconcentration of children from poor families."

Consider, for example, peer influences. It is a disadvantage to haveclassmates who misbehave, cut class, miss school, engage inviolence, watch excessive television, drop out, and fail to go onto college. Research finds that all these behaviors track much moreclosely by economic class than by race. There is powerful evidencethat even the widely discussed phenomenon in black communities ofdenigrating academic achievement as "acting white" is, in fact, aphenomenon more deeply rooted in class--common among low-incomestudents of all races.

Evidence like this convinced officials in Wake County to giveincome-based integration a try. Starting in 2000, they began toassign students--largely through public school choice and redrawnschool lines--to ensure that no school had more than 40 percent ofstudents eligible for subsidized lunch (an indicator of lowparental income) or more than 25 percent of students achievingbelow grade level.

The results have been promising. In 2005, low-income and minoritystudents substantially outperformed comparable students in largeNorth Carolina districts that have greater concentrations of schoolpoverty. Other districts using socioeconomic integration, like LaCrosse, Wisconsin, have also seen rising academic achievement.

Of course, schools are about more than boosting test scores. In anation made up of peoples from all across the world, U.S. publicschools have a special role in promoting tolerance and socialcohesion--so racial integration is an important goal, whatever itseffect on academic achievement. But on this score, too, Wake'ssocioeconomic program has been a success. Under a previous racialintegration policy, in the 1999-2000 school year, 64.6 percent ofWake County schools met guidelines providing that all schoolsshould be between 15 and 45 percent minority. Two years later,under the new socioeconomic integration policy, 63.3 percent ofschools met those targets.

Socioeconomic integration should produce substantial amounts ofracial integration beyond Wake County. Begin with the fact thatblack and other minority students are almost three times as likelyto be low income as white students. Moreover, because of housingdiscrimination, poor blacks are more likely to live in concentratedpoverty and attend high-poverty schools than poor whites. The CivilRights Project at Harvard University found that, in the 2003-2004school year, 76 percent of predominantly minority schools were highpoverty, compared with only 15 percent of predominately whiteschools.

The harder question is what to do when the circle can't be neatlysquared. What about a district that has a large black middle-classpopulation, or a substantial low-income white population, wheresocioeconomic integration alone does not produce sufficient racialintegration? Rather than rule definitively against the use of race,the U.S. Supreme Court would be wise to allow school districts toemploy it as a last resort--a policy used in the Cambridge,Massachusetts, public schools. Cambridge seeks to integratestudents principally by socioeconomic status, but it reserves theright to also make race a determinative factor if socioeconomicintegration does not produce sufficient racial diversity. In thefour years since Cambridge adopted the socioeconomic model,economic integration has, by itself, brought racial diversity, andno student has been denied a spot because of race.

But unlike Seattle and Louisville, which go directly to using racein student assignment, Cambridge attacks the fountainhead ofinequality--the separation of rich and poor. An emphasis onsocioeconomic integration addresses, at long last, issues ofeducational inequality at their most profound level. If the Courtstrikes down the use of race, socioeconomic integration is likelyto be the best way to produce racial integration as well.

By richard d. kahlenberg