This story was produced by The Hechinger Report, a nonprofit, independent news organization focused on inequality and innovation in education.

When Lauren McKinnon heard a new public elementary school was opening close to her home in Dallas, it was good news; but when she learned the school would offer an all-girls education format with a focus on STEM, she was excited, knowing inequities often exist for girls – like her daughters – in math and science.

But something else stood out about the school that attracted McKinnon: its potential for a student body that looked more like Dallas as a whole.

The school, Solar Prep for Girls, opened in 2016 as a “Transformation School”, one of several efforts underway to reverse decades of white flight from the school system. The school district is currently 71% Hispanic, 21% Black and 5% white, and 86% of its students are eligible for federally subsidized lunches.

In contrast, the city of Dallas is more evenly divided racially and ethnically: It’s 41% Hispanic, about 29% white and 24% Black.

Solar Prep and other “50/50” schools in Dallas have no attendance boundaries. Students are admitted by lottery, with some seats open to families who live outside of the school district. Half of the students admitted must live in one of Dallas’ socioeconomically disadvantaged census blocks, while the other half are drawn from more affluent areas. The district provides transportation to students within its boundaries.

The district currently has 13 such schools. As a group, these 50/50 schools draw thousands of applicants and have proven so popular that the district plans to open 11 more over the next three years, including two that will open when the school year resumes Aug. 15.

“I’m Caucasian and I grew up in a lower socioeconomic group, so I know that color does not equate to income, but in Dallas, our hypothesis was that we were going to get some diversity,” McKinnon said. “We got lucky with Solar and haven’t looked back.”

The demographic breakdown at Solar Prep for Girls, where McKinnon’s daughters Elizabeth and Vivienne attend first and second grade, respectively, is 20% white, 17% Black and 52% Hispanic.

The district sees its 50/50 Transformation Schools as one way to eliminate pockets of concentrated poverty and slow down enrollment declines.

“The city of Dallas is so segregated that, by using the 50/50 model, we can easily achieve racially diverse schools,” said Nancy Bernardino, a co-founder of Solar Prep for Girls. “We can’t admit by race, but this approach has given us that opportunity.”

Solar Prep for Girls was the district’s first 50/50 school. To get that diverse mix, the district uses the most recent census tract data available to create a socioeconomic map, and then places each of the city’s 827 census blocks in one of five buckets. The first bucket represents the wealthiest neighborhoods and the fifth represents the poorest.

The calculus that the school district uses to determine economic status includes median income along with other factors, such as parental level of education, home ownership and single parent status. Research shows that kids from both low-income and affluent families do better in school when they’re in socioeconomically mixed classrooms. Dallas school leaders are finding that these deliberately diverse schools are popular with parents on both ends of the spectrum.

Martha Castro, whose youngest daughter Sofia is in second grade at Solar Prep for Girls, said the school culture has made a noticeable difference in her daughter.

“She stands up for herself and speaks out when she doesn’t like something,” said Castro, a single parent who works as a housekeeper. “Since the school opened, I wished one of my daughters could go there,” she said, but her older children were already in high school.

Castro, who is Hispanic, likes the way teachers at the school encourage the girls to believe that “they can do whatever they want in life.” Castro and her daughters live 30 minutes away in Mesquite, a suburb east of Dallas.

“I have never seen her more confident,” Castro said. “I truly believe that’s because of the school.”

The district’s attempts to achieve a measure of integration while avoiding specific racial quotas have received national attention.

“A lot of school districts that have very few white or middle class students give up on integration, which I think is a mistake,” said Richard Kahlenberg, director of K-12 equity and a Senior Fellow at the Century Foundation. “With DISD’s demographics, a lot of outsiders would say that integration is irrelevant. Dallas thankfully proved them wrong because they looked at the metropolitan area, rather than just the existing school population, and thought more broadly about the possibilities.”

The district also sees the program as a way to slow down the number of students leaving the system. Like so many urban districts, DISD enrollment is declining steadily — by more than 10,000 since the 2018-19 school year. DISD’s experiment to reverse decades of segregation and student population loss enrolls just under 6,000 students — a small district within a district.

DISD, like many school districts, shies away from integration efforts that explicitly take race into account. In 2007, the U.S. Supreme Court ruled against districts in Seattle and in Jefferson County, Kentucky, which had used a “racial tiebreaker” to achieve racial balance in some of their schools. Such a policy was a violation of the equal-protection clause of the 14th Amendment, the court said in a 5-4 decision.

“The way to stop discrimination on the basis of race is to stop discriminating on the basis of race,” Chief Justice John Roberts wrote for the majority.

The court decision did not forbid race from being a part of school integration efforts, but said that such efforts face “strict scrutiny” and must be “narrowly tailored.” Since that decision, guidance from the federal Department of Education, which does not carry the weight of law but is often relied upon by school districts, has varied, changing with the occupant of the White House.

The Obama administration, for example, released a document outlining ways that districts could take race into account in school admissions policies without running afoul of the law. Then, during the Trump years, the department rescinded that guidance, saying it went too far. As a candidate, President Joe Biden said that he would remove the Trump-era guidance, but the department has not issued new guidelines.

Dallas isn’t the only district that uses a “diversity by design” approach. Louisville — one of the districts whose integration policy was struck down in the 2007 Supreme Court case — places schools in geographic clusters of diverse neighborhoods based on census block characteristics, including household income and adult educational attainment. Since 2001, Cambridge, Massachusetts has used a “controlled choice” socioeconomic school assignment model.

In Dallas, historic and ongoing residential segregation, concentrated poverty and competition from charter schools pushed the district to innovate. Residentially, it’s one of the most segregated large cities in the country. While north Dallas is mostly white, most Black Dallas residents live in south Dallas. Both east and west Dallas are deeply Hispanic.

Segregation concentrates Black and Hispanic students in high-poverty schools, said Sean Reardon, professor at Stanford University’s Graduate School of Education. Using data from every school district across the country, Reardon tracks educational outcomes, economic status and race. As schools become more segregated, gaps in learning rates widen, he said. Where there are achievement disparities, they can be explained by the fact that in segregated districts, Black and Hispanic children generally attend high-poverty schools, while white students generally attend low-poverty schools, Reardon said.

“There’s nothing magical about the whiteness of classmates in integrated schools that rubs off and improves test scores,” said Kahlenberg, with the Century Foundation. “It’s the concentrations of poverty that are troubling.”

In 2014, DISD officials opened the Office of Transformation and Innovation to tackle the problems of enrollment declines and segregation. The district surveyed parents to find out what kind of schools they wanted. Among the most popular choices were college prep, Montessori and international baccalaureate programs. The district added single-gender and STEM schools to that list to create a portfolio of new, thematically appealing schools that use a 50/50 socioeconomic diversity enrollment formula.

But successful school integration, said Bernardino, the co-founder of Solar Prep for Girls, isn’t just about enrollment. Before opening the school five years ago, Bernardino visited socioeconomically diverse schools in other cities. What she saw was that putting a diverse group of children together in a classroom isn’t enough on its own to change outcomes.

“When we went to visit these schools, they were diverse, but the practices were still very traditional,” Bernardino said. “Students were self-segregating and adults still targeted certain children to come up and speak. These leaders thought that doing the lottery would be enough.”

During that planning year, Bernardino and her co-founder, Jennifer Turner, worked hard to get the word out about the school, visiting every Head Start program and day care center they could. It was easy to fill seats for both socioeconomic buckets the first year. But once the two co-principals were busy running a new school and didn’t have time for as much outreach, the number of applications from economically disadvantaged families declined. There weren’t enough to fill half of available seats, so the principals headed back out into the communities. They knocked on doors, set up booths at Cinco de Mayo and Martin Luther King Day events and helped families fill out applications.

“Moms need to meet me and feel a connection with the principal,” Bernardino said. “Letting their 4-year-old travel across the city and not knowing if they can get to her if something happens, that’s what they sacrifice. That was the biggest challenge.”