Some teachers and parents gave up hope that the Southwest Detroit Community School could recover from backsliding test scores and relentless administrative turnover.

So they left. Enrollment is down this year roughly 10 percent at the small K-8 charter school in Detroit, and only half of the teachers returned in the fall.

It’s a familiar story in Detroit, where one in three elementary students changes schools every year, often because parents respond to problems in the classroom by moving their child to a different — if equally troubled — school.

But a vocal group of parents and teachers arrived at a board meeting last week with a different message. They said they would stay at the school, but that they wanted the teachers — through their newly formed union — to play a greater role in the daunting task of turning around the school.

The school has only about 30 teachers, but their collective bargaining agreement, signed this summer, was a remarkable development in a Michigan charter school landscape viewed by many labor leaders as inhospitable to unions.

Their victory points a way forward for unions in charter schools and suggests that unions overall can overcome a string of political defeats by pitching themselves as the solution to problems that are deeply ingrained in Detroit schools.

The teachers’ successful organizing effort was based in part on convincing educators and school leadership that a union was an essential ingredient in turning around a struggling school. Five different principals have led the school since its founding in 2013, and teachers felt they could help stabilize the school.

Yet any hope of a team effort in turning around Southwest Detroit Community School has taken a serious hit in the first months of the school year. Union members allege that the management company, EAS Schools, violated the clause in their contract that would give them a role in hiring administrators.

Heather Gardner, president of EAS, denies that the company violated the clause, and she said she hopes the company can work with teachers to turn the school around.

Teachers’ “hard work in collaboration with administration’s vision and direction is what will allow the school to … successfully serve the children of Southwest Detroit,” Gardner wrote in an email.

But the current tensions make clear that they have competing visions for how to improve the academic performance of a school where fewer than one-third of students are reading or doing math on grade level.

The school’s low test scores have drawn scrutiny for state officials. It could face closure if it fails to hit improvement targets laid out in a contract with the state department of education.

Teachers say they’ve been shut out of decision making, and argue that the school will fare better if they have a seat at the table.

“We want to use our collective voice to establish stability within the school,” said Kammy Webb, a teacher and union member. She hopes that the union can give voice to the interests of both teachers and families, many of whom have been with the school since its founding.

“The teachers have been more constant here than the administration,” she said. “Our hope was to increase teacher retention by making sure that people feel they do have a voice. A lot of the decisions just felt like they were being made in a vacuum.”

Contributing further to the tensions, the union filed a formal unfair labor practice charge against EAS over the suspension of chapter chair Jacob Robinson.

Robinson was put on administrative leave with pay last week pending an investigation. Gardner says Robinson shared details from a meeting with administrators that she says was confidential. Robinson says it was his duty as an elected union official to share information about wages and hours with union members.

Educators at Southwest Detroit Community School join other teachers who have sought a greater voice in school-level decisions by forming a union despite recent policy shifts that some viewed as a death knell for organized labor at school.

Within days of the vote to form a union at Southwest Detroit Community School, the U.S. Supreme Court issued a decision in Janus v. AFSCME that effectively spread so-called “right-to-work” laws to every state in the country. The ruling meant that unions could no longer automatically deduct membership dues from workers’ paychecks, or collect dues from workers who were represented by the union in labor disputes but who chose not to be members.

Experts predicted that the decision would deal a painful blow to teachers unions nationwide. They pointed to declines in membership and fundraising in Michigan since the state passed its own version of “right-to-work” in 2012.

But the evidence also shows that teachers unions in “right-to-work” states like Michigan are showing signs of resilience despite membership declines, as leaders look for creative ways to win new members. According to research by education professors Bradley Marianno and Katharine Strunk, Janus could “cause union leadership to listen to their members in new ways.”

Nate Walker, a Detroit-based organizer and political analyst for AFT, said that the methods used in the organizing effort at Southwest Detroit Community School are not new.

“Teachers have fought long and hard to make sure they have a voice in their workplace, and that cuts across traditional and charter schools,” he said.

Still, some argue that efforts to give teachers a greater role in school policy might be uniquely suited to expanding unions’ presence in charter schools. In Detroit, just under 10 percent of charter schools are unionized, but it remains to be seen whether unions like the American Federation of Teachers will seek to offset post-right-to-work membership losses by expanding into charter schools, Marianno said. Walker declined to comment on the union’s plans.

Marianno said that using unions as a way to gain a voice in school-wide decisions could be especially effective in charter schools because teachers who are drawn to them are more likely to want to play a role in improving schools — and thus are more likely to join a union that lets them.

“Throughout labor’s history in education, they’ve made this call to expand beyond the bread and butter of wages and working conditions,” Marianno said. “On the whole it hasn’t really taken hold,” adding: “It’s a natural avenue given the differences between the charter sectors and traditional schools.”