(CNN)More than 30,000 Chicago Public Schools teachers and support staff will go on strike if they can't successfully negotiate a contract deal with the district by October 17, the Chicago Teachers Union said in a statement.
The statement late Wednesday quoted several union members.
"We don't want to strike, but we will if we have to," said special education teacher Linda Perales.
"Our students deserve smaller class sizes. They deserve nurses. They deserve social workers. They deserve bilingual educators," Perales said. "This is what we're asking for at the table, and we're willing to strike to get them for our students."
The union pointed to large class sizes, low pay for teaching assistants and a shortage of counselors, social workers and school nurses, making teachers' work harder than it already is. One teacher said her second-grade class had 40 students last year.
According to the union, nine of 10 majority-black schools have no teacher librarians, and there aren't enough teachers for English language learners in the district, which the union said is "nearly half Latinx."
The teachers union set the strike deadline after 94% of its members voted last week to authorize a strike, it said.
The union represents more than 25,000 educators.
Supporters cheer at the Chicago Teachers Union headquarters in Chicago on September 24.
Union leaders want to hold Mayor Lori Lightfoot accountable for promises she made during her campaign, they said at a news conference Thursday.
"The mayor of the city of Chicago ran for office making promises and commitments about basic educational supports, about equity, about transforming neighborhood schools," said Jesse Sharkey, president of the Chicago Teachers Union.
"We expect her to keep those promises and to put those commitments in writing," he said. "And if we can do that, then we're confident that we can reach and negotiate a settlement. That remains our focus."
School building will be open during strike, officials say
Chicago Public Schools officials said their offer includes a 16% raise over five years, according to CNN affiliate WGN. Officials plan to add 200 social workers and 250 nurses over five years to address staffing needs.
School and city officials have sent proposals to the union, Lightfoot said at a news conference Thursday morning, but the union hasn't responded.
"There's a lot that needs to be done and we can get it done," Lightfoot said. "But they need to come to the table with written, substantive proposals to respond to the offers that we have put on the table."
The city's first priority, she said, is the safety of the district's 360,000 students, many of whom depend on the schools for breakfast and lunch. "We want to make sure that their ability to get healthy food on a daily basis is not interrupted," she said.
In the event of a strike, classes will stop. But many CPS buildings will remain open for any students who need "a safe place to go," Lightfoot and CPS officials said in a statement.
"We have 360,000 children who depend upon CPS every single day to learn, to play, to grow and to be fed," Lightfoot told reporters. "And so when we think about a work stoppage, think about what that does for them."
