After a tense 24-hour stalemate that saw hopes raised and dashed of a possible deal, delegates for the Chicago Teachers Union voted 364 to 242 to approve a tentative contract Wednesday night. But that vote comes with a caveat: Chicago Mayor Lori Lightfoot must agree to let the members make up their missed days and earn their pay, teachers say.

In the meantime, the teachers say their strike will continue, entering an 11th day Thursday. Chicago Public Schools has canceled classes for its 300,000 students in district-run schools.

Speaking at City Hall Wednesday after the union’s House of Delegates vote, Lightfoot said she was “gravely disappointed” in the turn of events and said she did not plan to compensate teachers for days they were on strike.

“At some point, the negotiations have to end,” Lightfoot said. “(Union President) Jesse Sharkey came into my office, laid out six issues, and told me in response to my skepticism that they would not move the goalposts. He gave me his word.”

“At some point,” she said, “the negotiations have to end.”

Bargaining has waxed and waned for two weeks, and leaders of both sides have alternately appeared cautiously optimistic, non-committal and patently frustrated at what they see as political posturing at the bargaining table and in public.

Tuesday night, talks appeared stuck on teacher prep time and a host of ancillary issues that had received little attention, like teacher evaluations and banking sick time. 

A Tuesday night House of Delegates meeting to “take the temperature” of teachers, according to leaders, raised hopes that a deal was near, but ended with teachers saying they’d be on picket lines on Wednesday.

But in 24 hours, the mood changed again. The governing body was called to convene again Wednesday night. The 41-page tentative agreement members weighed lays out how the city would invest money in a committee to help reduce overcrowded classes and in hundreds of new social workers, nurses, and special education managers — some $70 million in additional staffing, all told. It also better guards counselors, special education classroom assistants, and teachers assistants from being called on to serve as de-facto substitutes, a chronic complaint on the picket lines. 

But the document, which also has provisions containing minutia about diapering and makeup of committees, lacked some of the union’s top priorities such as additional prep time for most elementary teachers.

Still, the majority of delates voted in favor of the agreement.

Stephanie Bradley, a social studies teacher at Kelley High School on Chicago’s South Side, said she cast one of the “yes” votes to end the strike. “We got a lot of wins,” she said, standing outside union headquarters after the vote. “It’s not perfect — but, overall, I think it’s something we can take back to our members that is solid. There’s never been anything guaranteed about class size, for example, and now there is some mechanism to enforce class size. Would I like to be better? Absolutely. But it’s a great start.”

Sharkey called the tentative agreement “a contract we can believe in” and listed several gains.

But he said one issue was preventing a return to work: making up lost days.

“We don’t understand why the mayor can’t simply call and say, We’ll give you an agreement to make up instructional time,” said Sharkey, who was flanked by union leaders and American Federation of Teachers President Randi Weingarten. “If the mayor calls and says we have an agreement on that, we’ll be back at work tomorrow. If she does not call, we’re continuing to be on strike.”

Minutes later, Chicago Public Schools posted a notice on social media that it was canceling classes for an 11th day.

Teachers are planning a 10 a.m. rally on Thursday at City Hall. Lightfoot said her team would be ready to return to the bargaining table.

Cassie Walker Burke contributed to this report.