CLEVELAND – Cleveland students returned to school Monday, the same day Cleveland Teachers Union officials declared plans to walk out on them over stalled contract negotiations.

The current contract between the CTU and Cleveland Metropolitan School District expired at the end of June, though it remains in effect until a new pact is crafted.

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Regardless, CTU President David Quolke called for a teachers strike to pressure district officials to accept its terms at the bargaining table, and the union’s executive committee approved the move Monday night, WKYC reports.

“We are disappointed to learn that the Executive Committee of the Cleveland Teachers Union has authorized a strike of its members. The District and CTU have been in negotiations since November 2015 and have spent hundreds of hours bargaining,” district spokeswoman Roseanna Canfora said in a statement.

“A significant number of items have been resolved, and only a few remain. It is unfortunate, therefore, that the CTU has chosen to put its efforts toward a strike rather than working to resolve the few remaining items,” she continued. “Nonetheless, the District is making preparations to minimize the impact on our 39,000 students. The Board remains committed to resolving any remaining issues without eroding school reforms critical to meeting the goals of The Cleveland Plan.”

The Cleveland Plan for Transforming Schools was approved by lawmakers in 2012 to implement changes in unionized schools aimed at improving poor academic performance by holding educators accountable for student learning, the Cleveland Plain Dealer reports.

The plan calls for a teacher pay model “based on performance” – an issue teachers unions strongly oppose – and the elimination of raises based solely on seniority. In the last union contract, signed in 2013, both sides agreed to dole out raises based on a variety of factors, but the Plain Dealer reports district officials have focused mostly on annual evaluations in the process.

“Ignored, so far, are contractually agreed items like teaching in hard-to-fill jobs or undesired schools; completing pre-approved courses and training that directly affect teaching; and taking steps to develop as a mentor and leader,” according to the news site.

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In other words, the union is upset because teacher raises are tied too closely to student test scores.

“We have an over-reliance on using these standardized tests to evaluate teachers,” Quolke told the Plain Dealer. “Money’s really not the issue at the table. It’s how we are living up to the promise of the Cleveland Plan.”

District teachers, who take home about $70,000 a year on average, can legally walk out on students 10 days after the union gives the district official notice of its intent to strike.

WKYC reports members voted to officially support a strike in May.

And aside from the threat of a teachers strike, the union is also holding an upcoming school tax renewal over the district to get what it wants in contract negotiations.

The 15-mill tax, originally approved by voters in 2012, is up for renewal on the Nov. 8 ballot and would generate about $55 million for the city’s charter and traditional public schools, The Plain Dealer reported in June.

“I still believe strongly that we can get this done,” Quolke said, “but we can’t keep kicking it down the road.”