BURLINGTON, Vt. – Teachers in Burlington, Vermont walked out on students this week to protest failed contract negotiations with the Burlington School Board after union officials rejected an offer for an 8 percent raise.

Burlington school board chairman Mark Porter, the district’s chief negotiator, told the Burlington Free Press the stalled contract talks centered on money, despite Burlington Education Association’s claim that the ongoing dispute centers on working conditions.

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“Money issues came up. We were told all along it wasn’t about money,” he said.

Porter said the district offered teachers an 8 percent raise over three years, but it apparently wasn’t enough.

Burlington Education Association President Fran Brock, meanwhile, continues to insist the strike, which began Thursday morning, is centered on elementary school working conditions.

“We’ve been trying to get the board to understand that elementary teachers are having too much of their time drawn away from one-on-one interaction with students. And now, for more than three years, they still won’t budge,” Brock said.

“We spent pretty much the whole day here trying to work with the school board,” she said Wednesday evening as she exited the law offices of McNeil, Leddy & Sheahan, where negotiations took place. “The problem comes down to their not really listening to us.”

Brock told WCAX the union wants a two-year contract that relieves elementary teachers of lunch and recess duties that used to be performed by other school staff. She alleged the work distracts from class preparation.

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“Teachers need to have the time to work both in creating and preparing lessons, and services and programs to our students,” she said.

School board member Stephanie Seguino countered that teachers are best suited to chaperone students during lunch and recess.

“Teachers know the students best,” she said. “And when teachers are not present in these areas, such as lunch and recess, we see problems with bullying emerge.”

She said the district offered average raises of about $6,000, the state’s benchmark health insurance plan and the elimination of some supervision duties, but the union wasn’t interested.

“The BEA then raised issues around salary and health care,” Seguino told WCAX. “We made proposals; they were not accepted. We didn’t receive counterproposals.”

School officials canceled classes and all other school activities for Friday, and there’s currently no plans on when teachers might return to their classrooms. Instead, they spent the day toting picket signs in front of local schools.

“People I represent – the parents, the kids, the businesses in this community – are being hurt by this strike,” Burlington’s Democratic mayor, Miro Weinberger, told the news site.

WCAX reports that statewide, teacher salaries increased by 74 percent over the last decade, while the average salary in Vermont went up by only 29 percent. In 2015, the median pay for Burlington teachers was $69,570, compared to the median household income in Burlington of $44,671.