Teachers and staff from the District’s Chavez Prep Middle march to the Mount Pleasant Neighborhood Library on Tuesday as they protest what they say is the school’s excessive spending on a consultant. (Michael S. Williamson/The Washington Post)

A rare battle between teachers and administrators at a charter school has broken into public view, with educators taking to the streets of a D.C. neighborhood to press their case that the school is spending millions of dollars on consultants while cutting core classroom positions.

The teachers at Chavez Prep Middle — the first D.C. charter school to unionize — say the administration’s spending is hurting students, who predominantly come from low-income, Hispanic families.

The teachers voted in June to unionize and are represented by the American Federation of Teachers. The three other campuses in the D.C. Cesar Chavez charter network are not unionized. The protest unfolded as teachers at Chavez Prep Middle are negotiating their first contract with school leaders.

“We want to make sure our students are as best served as possible,” said Do Lee, an eighth-grade math teacher. “But a lot of our money is going to the [consulting firm], and we don’t see the trickle-down effect.”

The leaders of the Cesar Chavez charter schools say the consulting firm is needed to boost the lagging performance of students and that the schools risk closure if their academic standing does not improve.

Charter schools are publicly funded and privately run, and unlike the traditional public school system, their teachers are not typically unionized. Massive teacher protests have been organized by unions in states such as Oklahoma and West Virginia this year, but they have emerged from the states’ traditional public school systems, with thousands of teachers represented by a single union. At Chavez Prep Middle, 30 teachers are in the union.

Nearly 7,000 charter schools serve 3 million students in the country, according to the National Alliance for Public Charter Schools. The American Federation of Teachers says that in the past year, teachers at more than a dozen charter schools nationwide have voted to unionize.

School leaders at Chavez said the union is misrepresenting the staffing cuts and the role of the consulting firm — and argue that it is a necessary investment for the school.

The Cesar Chavez network has a four-year, $5.3 million contract with TenSquare, a consulting firm that supports charter schools, according to school leaders. The annual budget at the four schools combined is more than $26 million.

Enrollment and standardized test scores have declined in recent years in the Chavez network, and the D.C. Public Charter School Board said in December it would close the schools if they don’t improve their academic performance, according to the board’s 2017 review. The board ordered the Chavez network’s Parkside Middle to be shut down over the next three years. The charter network schools have experienced high turnover in their administrations.

Network administrators say they brought in TenSquare to help turn around the schools.

“The goals for TenSquare’s efforts within the Chavez network require a sustained effort,” Rick Torres, the network’s board chairman, wrote in a statement. “The good news is that we are already seeing encouraging signs of improvement thanks to the dedication of our teachers and staff and the support of TenSquare’s specialists in the areas where Chavez needs additional help to support our students and families.”

TenSquare founder Josh Kern said his consulting firm has 12 employees working across the four campuses. He said the firm trains school leaders, coaches and teachers and works with struggling students. TenSquare is working with three other D.C. charter schools, and Kern said client schools see dramatic improvements in their charter board evaluations. The firm also works with schools in New Orleans and Las Vegas.

“The work we are doing is essential to the school,” Kern said, “and absolutely necessary to improving the school.”

The unionized teachers at Chavez Prep Middle have already scored a small victory: The National Labor Relations Board found merit in March to allegations that Chavez school administrators are making changes to the workplace without negotiating with the teachers. An administrative trial is set for this summer.

Chavez Prep Middle teachers who protested Tuesday said they are angry that the administration is not filling vacant positions for a social studies teacher and a teacher of English as a second language. The Columbia Heights middle school campus has a large population of Hispanic students, and teachers said the English-language position is critical. The loss of these positions, they argued, leaves the staff stretched thin.

But school leaders said they had to make those cuts because of declining enrollment. The schools receive city funding for each student enrolled, and the four campuses went from 1,420 students in the 2015-2016 school year to 1,172 students this year, according to data from the D.C. charter board.

The protesting teachers marched from the middle school campus in Columbia Heights to the Mount Pleasant Neighborhood Library, where some of the teachers met with school leaders to continue contract negotiations. Representatives from TenSquare were present at the negotiations.

The educators carried signs invoking the philosophies of the school’s namesake, Cesar Chavez, a Mexican American farmworker who became a national labor leader.

“What would Cesar do?” one sign read. Protesters chanted “TenSquare, escucha, estamos en la lucha,” which translates from Spanish to, “TenSquare, listen, we are in the fight.”

“It seems to us that TenSquare is coming in and exploiting a broken evaluation system to fill their pockets,” said Christian Herr, a science teacher at the school and one of the union leaders.