PIKE ROAD, Ala. — Pike Road High School graduates its first senior class this school year, and leaders of this sprawling, semi-rural suburb of Alabama's capital city extol the young community's focus on education as one of its defining elements.

"We are extremely proud of where we are," said Pike Road Mayor Gordon Stone. "We're competing well in every area that you measure from academics to athletics."

Pike Road pulled out of the Montgomery County school district in August 2015, leaving the much larger district even more heavily African American than it was before. And Pike Road is not alone. A new study finds that the carving out of new school districts in the South is increasingly dividing white students from their black and Latino peers, reinforcing segregation.

Pike Road High School in Pike Road, Ala., on Sept. 3, 2019. Jeff Amy / AP

"It can help draw boundaries around white spaces," said Erica Frankenberg, a Penn State University professor who is one of three authors of the study, published Wednesday in AERA Open , a journal of the American Educational Research Association.

Those who study the creation of new school districts call the exits secession, conscious of the

Civil War overtones that has for districts in the South. The issue is particularly important, Frankenberg says, because the U.S. Supreme Court ruled in 1974 that courts couldn't order desegregation across district lines. That means that while an individual district may be able to find ways to more effectively integrate students, district lines usually pose fatal obstacles to such efforts.

The study examines 18 districts created since 2000 across Alabama, around Baton Rouge, Louisiana, and around Memphis, Tennessee. The study found that an increasing share of segregation between black and white students was caused by district lines as opposed to clustering at specific schools within a district.

In Pike Road, just over half of students were white last year, while about 30% were African American. The remainder were Asian, Hispanic or multiracial. That's a higher share of black students than other suburban districts around Montgomery seen as alternatives to Pike Road.

The system's leaders point to that diversity, which roughly mirrors schools statewide across Alabama, to argue they're not a white-flight suburb. Superintendent Chuck Ledbetter said some students came to Pike Road from private schools that were much more likely to be overwhelmingly white.

"They had essentially self-segregated by going to the private school and have made a choice that leads to integration, to be part of a more integrated system than most of the private schools are," Ledbetter said. "For those parents I don't think it was about segregation or integration. I think it was about looking for quality schooling."

Karla Webb's two children are too young for school, but she said her daughter will start kindergarten at Pike Road's elementary school next fall. Webb, who is white, said the school system has "brought the community together in a way no other aspect of Pike Road has" and that if the town hadn't created a school system, her children would have probably been bound for private school. She said some friends teach in Montgomery County, and she hears good things about elementary school but is worried about middle and high school and uncertainty after the state took over some district affairs because of financial problems and poor academic achievement.

"Montgomery Public Schools needs some intervention and we can't tell whether it's getting it or not," Webb said.

In the Montgomery County district nearly 80% of its 28,000 students last year were black, in large measure due to the population within the district. But the study finds that Pike Road, with 2,000 students, also is contributing to segregation in the larger system. The share of white students has fallen significantly in the Montgomery County schools where Pike Road students formerly attended. Park Crossing High School was 17% white before Pike Road seceded and only 5% white last year. Blount Elementary School was 47% white, while last year it was 37%.

Dawn Chapman, a former teacher in the Montgomery County schools, said she considered sending her son to the larger county system but was worried about its fit in terms of learning style. Chapman, who is African American, also said she didn't want her child to attend an overwhelmingly black school.

"I wanted him to go somewhere that was more diverse," said Chapman, who enrolled her son at Pike Road's elementary school. She said she worries about how students in the county school system will fare without exposure to children of other races.

"It has a huge effect, knowing how to interact with people from different races," she said.

Beyond racial overtones, those who study secessions say there's also a resource disparity. Voters in Pike Road agreed to a property tax increase, and the school is spending $10 million to renovate its high school, a historically black campus that it bought from Montgomery County for another $10 million.

"We saw in a single year, that these secession areas as a whole were overwhelmingly whiter and wealthier," said Rebecca Sibilia, the executive director of EdBuild, a school funding advocacy group that has studied the fragmentation of districts.

In Alabama, any city with more than 5,000 residents can walk out of its countywide school system with a vote of the city council. But in Tennessee, constituents had to persuade lawmakers to lift a ban to allow school systems to separate from a district that temporarily included Memphis and its surrounding county. In Louisiana, voters statewide must approve a constitutional amendment for each system.

Ledbetter acknowledges that white parents have long been fleeing the Montgomery County system, followed in some cases by African American parents with the means to move. He argues that Pike Road, especially as new as it is, isn't responsible for that flight.

"People are making choices," Ledbetter said. "Pike Road is not the reason people are making a choice. Pike Road is another choice."