chicago teachers
Chicago Teachers Union members picket outside of the Chicago Public School headquarters on the fourth day of their strike in Chicago, Sept. 13, 2012. John Gress/Reuters

The Chicago Teachers Union on Thursday called an end to its 11-day-old strike and classes for 350,000 students from preschool through high school and 21,000 teachers were set to resume Friday.

Mayor Lori Lightfoot announced the settlement following a two-hour meeting with union leaders. The union’s House of Delegates approved a contract Wednesday but a disagreement over adding make-up days prevented classes from resuming Thursday.

The union confirmed the announcement on Twitter.

Dozens of teachers demonstrated around City Hall in wintry weather as the talks continued. The strike was the longest in Chicago Public Schools history, and the contract still needs the approval of rank-and-file teachers.

“We’re showing the city that we mean business,” said Bill Weeks, a special education teacher at Foreman College and Career Academy.

Lightfoot initially refused to discuss adding days to the end of the school year, saying the union kept moving the finish line.

“CTU leadership has chosen to throw a curveball into the process rather than say ‘yes’ to victory for the members and our students,” Lightfoot said.

The final agreement will add five make-up days.

“The question that everyone wants to know is, are we ending the strike and returning to work?” union President Jesse Sharkey said ahead of Thursday’s talks. “And the answer to that is, we want to, but there needs to be a discussion about making up some of the instruction time that was lost.

“I understand that it’s going to be difficult for the mayor and for the people who run the schools to fit 11 instructional days back into the school year. But our strong feeling is that we want to discuss it. It can’t be zero [days]. It can’t be zero. That’s not an acceptable number to us.”

The teachers’ contract provides for a 16% pay hike over five years, limits on classroom size and funding for social workers and nurses at some schools. It does not include extra prep time for elementary school teachers, which had been a key talking point.