As city officials confirmed that classes will be cancelled for some 300,000 Chicago public school students when teachers are expected to strike on Thursday morning, Chicago’s mayor Lori Lightfoot said that she was focused on getting a fiscally responsible deal done and making sure students out of school had a safe and warm place to go during the strike. 

In her first public appearance since a Tuesday night union conference where leaders said a strike was all but inevitable, Lightfoot still stuck by her negotiators and said her team has done its best to avert a strike. 

“We have worked hard at the table to listen to the union’s concerns,” said Lightfoot, who lauded the city’s pay offers. “We have tried to provide the best deal that is fiscally responsible.” 

The Chicago Teachers Union has pushed beyond pay at the bargaining table and used contract negotiations to advocate for a broader agenda that includes widened support services and better resources. 

After agreeing in recent days to a union demand to write staffing and class size promises into the union contract, Lightfoot said city negotiators had bent over backward to offer pay raises and meet union demands on control over teacher prep time. 

On the heels of the mayor’s press conference, the union claimed Wednesday morning that  Lightfoot would not actually lower class sizes nor make size caps enforceable. The union also said it has failed to win agreement on staffing ratios for counselors, social workers and other staff. 

When teachers walk out on Thursday, as their leaders say will happen, they will stage the third citywide teachers strike in less than a decade. 

The mayor said she was sympathetic to striking workers, but said the union has not been bargaining with enough urgency to avoid a strike. “I’m the daughter of a union steelworker. I am a strong believer in the power of collective bargaining, and when it comes down to it, the right to strike,” Lightfoot said. 

In response to a reporter’s question about whether she would consider filing an injunction with the labor relations board, which could stall a teachers strike, Lightfoot said she was focusing on negotiations today. 

The mayor was joined on Wednesday by board president and longtime progressive Latino leader Miguel del Valle, who said he was disappointed that the strike was moving forward. 

The school district also faces a threatened strike Thursday by support staff and park district workers, two groups who had in the past cared for students during teachers strikes. 

Schools chief Janice Jackson said classes would be cancelled but students could attend any age-appropriate school in their area, where they would be supervised by administrators, non-union staff and central office staff. District leaders were encouraging families to register on the school system’s website if they planned to attend schools, so that buildings could be staffed appropriately.