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May 1, 2013

Boosting Achievement by Pursuing Diversity

What can we learn from schools that are improving student achievement by breaking up concentrated student poverty?

One morning last December, a crowd gathered at the Thomas B. Fordham Institute in Washington, D.C., for a discussion on school turnaround. Panelists debated whether the best way to fix persistently underperforming schools was simply to replace the administrators and teachers at the school, or whether reopening under new charter management was the only effective option.

But what if, instead of changing the principal, teachers, or management in the hope that this will turn around a high-poverty school, we changed the mix of students, rebalancing enrollment so that the school did not serve a concentration of the most disadvantaged students? When asked this question, panelist Carmel Martin, assistant secretary for the U.S. Department of Education, said, "I think it's a really important question." But she quickly added, "We're focused on governance and the people [adults] in the building, which we think are critical ingredients."

Although few policymakers and wonks are talking about it, a small but growing number of schools are attempting to boost the achievement of low-income students by shifting enrollment to place more low-income students in mixed-income schools. Socioeconomic integration is an effective way to tap into the academic benefits of having high-achieving peers, an engaged community of parents, and high-quality teachers.

In the last decade, the number of public school districts that consider socioeconomic status in student assignment has grown from just a handful to more than 80 (Kahlenberg, 2012). Early adopters included La Crosse, Wisconsin, which created a districtwide plan to balance school enrollment by socioeconomic status in 1979, and Cambridge, Massachusetts, which made socioeconomic status the main factor in its controlled choice program in 2001. Newer additions include Bloomington, Minnesota, and Salina, Kansas, both of which used socioeconomic balance as a factor in redrawing school boundaries in recent years.

Adding to this list, a number of charter schools now actively seek socioeconomically diverse student enrollment as part of their design. They include schools like High Tech High, which began in 2000 as a single charter school and is now a network of 11 schools in San Diego, and Citizens of the World Charter Schools, which opened its first school in 2010 and is striving to create a national network of diverse charter schools.

Going against the grain in a country where many public schools are de facto segregated by income, these socioeconomically integrated charter schools have developed innovative methods for enrolling and serving a diverse student body.

The Case for Socioeconomic Integration

On average, students' socioeconomic backgrounds have a huge effect on their academic outcomes. But so do the backgrounds of the peers who surround them. Poor students in mixed-income schools do better than poor students in high-poverty schools.

Research supporting socioeconomic integration goes back to the famous Coleman Report, which found that the strongest school-related predictor of student achievement was the socioeconomic composition of the student body (Coleman et al., 1966). More recent data confirm the relationship between individual achievement and student-body characteristics. A 2010 meta-analysis found that students of all socioeconomic statuses, races, ethnicities, and grade levels were likely to have higher mathematics performance if they attended socioeconomically and racially integrated schools (Mickelson & Bottia, 2010). And results of the 2011 National Assessment of Educational Progress in mathematics show steady increases in low-income 4th graders' average scores as the percentage of poor students in their school decreases (U.S. Department of Education, 2011).

Of course, multiple non-school-related factors could explain why low-income students in mixed-income schools outperform their counterparts in high-poverty schools. Students attending mixed-income schools might be more likely to have involved parents or live in a more affluent community, for example. However, a number of studies have found that the relationship between student outcomes and the socioeconomic composition of schools is strong even after controlling for some of these factors, using more nuanced measures of socioeconomic status, or comparing outcomes for students randomly assigned to schools (Reid, 2012; Schwartz, 2012).

Socioeconomic integration improves student outcomes because mixed-income schools are more likely to have certain resources or characteristics that foster achievement. Rumberger and Palardy (2005) found that the socioeconomic composition of the school was as strong a predictor of student outcomes as students' own socioeconomic status. However, the researchers found that the advantages of attending a mixed-income school could be fully explained by school characteristics such as teachers' expectations, students' homework habits, and school safety. They concluded that high-poverty schools could work "if it were possible to alter those policies and practices that are associated with schools' socioeconomic composition" (p. 2021).

That if is a serious caveat. High-performing, high-poverty schools are very rare. The economist Douglas Harris (2007) calculated that only 1.1 percent of majority-low-income schools consistently performed in the top third of their state. Further, to the extent that the biggest advantage of socioeconomic integration may be direct peer effects (Reid, 2012)—picking up knowledge and habits from high-achieving, highly motivated peers—high-poverty schools will always be at a disadvantage, given the strong relationship between students' own socioeconomic statuses and their academic performance.

Socioeconomic integration is a win-win situation: Low-income students' performance rises; all students receive the cognitive benefits of a diverse learning environment (Antonio et al., 2004; Phillips, Rodosky, Muñoz, & Larsen, 2009); and middle-class students' performance seems to be unaffected up to a certain level of integration. Research about this last point is still developing. A recent meta-analysis found "growing but still inconclusive evidence" that the achievement of more advantaged students was not harmed by desegregation policies (Harris, 2008, p. 563). It appears that there is a tipping point, a threshold for the proportion of low-income students in a school below which middle-class achievement does not suffer.

Estimates of this tipping point vary; many researchers cite 50 percent low-income as the maximum (Kahlenberg, 2001). However, in a report that Richard Kahlenberg and I coauthored for the Century Foundation, we profiled diverse charter schools in which the proportion of low-income students (as measured by eligibility for free and reduced-price lunch) ranged from 30 to 70 percent, within 20 percentage points of the 50 percent goal (Kahlenberg & Potter, 2012). The findings suggested that, more than a precise threshold, what mattered in these schools was maintaining a critical mass of middle-class families, which promoted a culture of high expectations, safety, and community support.

Lessons from Socioeconomically Diverse Charter Schools

Despite the evidence of their advantages, socioeconomically integrated schools are not the norm in the United States. In traditional public schools, 65 percent of low-income students are concentrated in majority-low-income schools. In charter schools, that figure is 78 percent (Frankenberg, Siegel-Hawley, & Wang, 2010).

Many choices have led to our economically segregated school system.<FOOTNOTE><NO>1</NO>See Richard Rothstein's article in this issue for a discussion of the societal causes of segregation in U.S. schools.</FOOTNOTE> Districts have chosen to let school boundaries reflect or even amplify residential segregation. Reformers have chosen to focus more on fixing high-poverty schools than on breaking up concentrations of poverty. Policymakers and philanthropists have favored interventions targeted at reaching as many low-income students as possible. But de facto school segregation also persists because balancing student enrollment by socioeconomic status, like most education reforms, is logistically, politically, and operationally difficult.

Socioeconomically diverse charter schools are developing practices to overcome some of the challenges of enrolling and serving a diverse student body. They have identified strategies that could help other schools and districts create successful integration programs.

Enrolling a Diverse Student Body

One of the foremost logistical barriers to integrating schools by socioeconomic status is geography. Residential poverty tends to be concentrated, and successful school integration requires either a district with enough socioeconomic diversity within its boundaries or a group of neighboring districts which, when combined, have enough diversity to facilitate an interdistrict integration plan. The availability of these geographic opportunities varies widely in states across the country (Mantil, Perkins, &amp; Aberger, 2012).

Some diverse charter schools were started by first identifying a geographic opportunity for integration that traditional public schools were neglecting. For example, Blackstone Valley Prep Mayoral Academy serves four adjacent Rhode Island communities, drawing students evenly from two higher-income suburbs and two lower-income cities. Larchmont Charter School in Los Angeles, California, was started by a group of parents from Hollywood who were frustrated that the demographics of their community, one of the most diverse neighborhoods in L.A., were not reflected in the area's schools.

Political opposition to adjusting attendance boundaries is another challenge. In Wake County, North Carolina, frequent student reassignments created controversy over the school district's long-standing socioeconomic integration plan. Opposition culminated in 2010, when a Tea Party–backed majority on the school board voted to end the plan. This group, however, was replaced in the next election by a prointegration majority. Similar backlash greeted a new school-boundary plan in Eden Prairie, Minnesota, that also balanced students by socioeconomic status.

Some charter schools pursuing socioeconomic integration have shown how systems of school choice can be used to foster diversity as an alternative to redrawing attendance zones. A weighted lottery is the simplest way for schools to ensure that they enroll a diverse student body while still relying on choice-based enrollment. For example, DSST Public Schools, a network of charter middle and high schools in Denver, Colorado, reserves a minimum of 40 percent of seats at the flagship campus for low-income students; Blackstone Valley Prep in Rhode Island reserves 60 percent of seats. High Tech High weights admissions lotteries in its elementary, middle, and high schools by students' home zip codes, which creates socioeconomically, racially, and ethnically diverse student bodies because of housing patterns.

Choice-based schools can also maintain a diverse balance by intentionally targeting underrepresented groups of students when publicizing their school. Capital City Public Charter School and E. L. Haynes Public Charter School are both located in Washington, D.C., where weighted lotteries are not permitted. Both schools maintain socioeconomically diverse enrollment through strategic recruitment for the lottery pool. E. L. Haynes, for example, receives many applications from middle-class families who proactively seek information because of the school's reputation, and it therefore directs all its recruitment efforts—from distributing information outside grocery stores to speaking at neighborhood association meetings—to low-income communities.

Serving a Diverse Student Body

Once an integration strategy is in place, schools and teachers must also adapt to serve a diverse group of students. Mixed-income schools can draw criticism from both directions with respect to how well the school community and individual classrooms are integrated. On the one hand, students in diverse schools are sometimes separated into tracked classes along lines that mirror socioeconomic status, and students may further self-segregate during free time. In that situation, middle-income and low-income students are cheated out of some of the peer interactions and access to broader social networks that diversity can offer. On the other hand, schools that intentionally maintain heterogeneous classes must consider the research suggesting that these classes can negatively affect the academic progress of higher achievers (Brewer, Rees, &amp; Argys, 1995).

Individual success stories and a review of research suggest that it is possible, by offering all students a single challenging curriculum, to reduce the achievement gap without harming the highest achievers (Burris, Wiley, Welner, &amp; Murphy, 2008; Rui, 2009). However, ability grouping remains a hotly debated topic that is particularly relevant at socioeconomically diverse schools, where students enter school with a wide range of knowledge and skills (see Petrilli, 2012). How can mixed-income schools best support lower-achieving students without hurting the higher achievers?

High Tech High and City Neighbors Charter School have innovative strategies for blending the benefits of leveled instruction and heterogeneous classrooms. High Tech High is committed to grouping students by mixed ability as much as possible. "It's not just diversity in admissions," said CEO Larry Rosenstock. "It's also integration in practice once they've arrived." Leaders at High Tech High realized they needed to offer honors classes so that students could have the weighted grade point averages that selective colleges look for in admissions, but they did not want to separate the highest-achieving students from their peers. Instead, they offer some classes with an honors option, allowing interested students to take the class at the honors level by completing extra assignments.

At City Neighbors Charter School, a K–8 school in Baltimore, Maryland, teachers regularly adjust student groupings to ensure that all students are appropriately supported and challenged. In the lower grades, students may sometimes be grouped into similar-ability reading circles; but for most assignments, they work in heterogeneous groups chosen for their members' complementary skill sets. Monica O'Gara, a 1st grade teacher and founding faculty member, described the range of student backgrounds as both a challenge and a resource: "There's quite a mix of what children understand and what approaches they're used to or will be effective with them." Although differentiation is a challenge for teachers, students of all backgrounds benefit from hearing about their classmates' experiences and from relating their own experiences to others.

In the middle grades, students at City Neighbors start their day with half an hour of highly specialized, small-group instruction called intensive. Intensive provides an opportunity for extra support or enrichment in different subjects, allowing teachers to meet different students' needs while still teaching most of the academic time in mixed-ability classrooms. For example, some students may spend their intensive time receiving extra writing support while others attend an enrichment intensive on animal dissection. Students cycle through different intensives three times a year, giving teachers multiple opportunities to adjust placements based on individual needs.

Some charter schools are also tackling the more elusive issue of how to encourage students of different backgrounds to interact socially. Community Roots Charter School, an elementary and middle school in Brooklyn, created a staff position—director of community development—to facilitate programs that promote community cohesion and celebrate diversity. Through the school's Play and Learning Squads, for example, small groups of students and their parents go on weekend or afternoon outings. Teachers assign the squads with an eye toward grouping students who would not otherwise spend time together outside school.

A Promising Direction

Academic results from these diverse charter schools are promising, if anecdotal. In our Century Foundation report, Richard Kahlenberg and I (2012) profiled seven diverse charter schools whose low-income students outperformed their low-income peers statewide in mathematics and reading, sometimes by dramatic —s. In all but one case, the schools' low-income students also beat the state proficiency averages for all students.

Many factors are at work in successful diverse charter schools. As schools of choice, these schools likely benefit from having a more engaged parent community than neighboring traditional public schools do. Still, when combined with the body of research showing the academic advantages of providing mixed-income learning environments, their stories are hopeful. If more schools, charter and otherwise, use creative strategies to tackle the challenges of socioeconomic integration, they can help shift the turnaround discussion from an exclusive focus on how to improve high-poverty schools to a discussion that also looks seriously at how to break up concentrations of poverty and provide more diverse learning environments for all students.


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