Unless they reach a compromise with their network bosses, teachers at 15 Acero charter schools will strike on Dec. 4. They announced the strike date Wednesday morning in response to a months-long stalemate over bargaining.

Acero Schools’ educators voted overwhelmingly to authorize a strike last month, with 98 percent of members who voted granting a strike authorization.

“Our working conditions are our students’ learning conditions,” said Andy Crooks, a special educator apprentice at Acero’s Sor Juana Inés de la Cruz school. “We were hoping the strike authorization vote would jar movement at the table, but we’ve had three meetings with management since that date, and there hasn’t been any significant steps toward progress.”

Teachers want higher pay, increased diversity among teaching staff in majority Latino schools, smaller class sizes and a shorter school year. The Acero school year began on Aug. 13, earlier than the post-Labor Day start at Chicago Public Schools.

Teachers said they hope the changes will stop the chronic staff turnover they argue is impacting their classrooms day-to-day.

Acero’s contract with teachers expired Aug. 2 and was extended until Oct. 3. The latest bargaining session took place on Monday evening and elicited little movement toward a contract, despite mediators already being present at the negotiations, said Crooks.  

Four more bargaining sessions remain until Dec. 4.

“There is room for both sides to give,” said Crooks.

In a statement to Chalkbeat, Acero officials said they would not leave the bargaining table until a resolution was reached. “While we are disappointed at the strike announcement, we are not entirely surprised. Based on statements CTU has made, there is a real focus on making an example out of charter schools,” the statement said. “Regardless, we are deeply committed to these negotiations for our students and our schools.”

Acero, formerly named UNO, is the largest unionized charter-school operator in Chicago Public Schools.

If teachers walk out, it will be the first strike of charter teachers in U.S. history.