A news conference is scheduled for 4:30 p.m. Wednesday afternoon.
Chicago Public Schools CEO Jean-Claude Brizard said he remained hopeful a deal will get done.
"This 10-day notice will put pressure on our kids, which we don't need, but we have been very serious about coming to a resolution as quickly as possible," said Brizard.
Nine months after talks began, the two sides remain at loggerheads over staffing for the longer school day and compensation issues.
The union wants automatic raises tied to teacher experience and is against any effort to tie increases to student performance, which school officials maintain they have not pushed.
"Too much of the reform agenda in Chicago is being driven by political considerations, not educators' considerations," said Jesse Sharkey, Chicago Teachers Union V.P.
Some teachers are also upset about issues separate from the talks including increased funding for non-union charter schools.
"I want Rahm Emanuel to take his ego, put it to the side, and really begin to think about what is in the best interest of our children," said Alyese Faibisoff, CPS teacher.
CPS has yet to reveal details of its plan to house and feed students in the event of a strike.
Also preparing is Pastor Walter Turner of New Spiritual Light Missionary Baptist Church who's working with other ministers to open at least 100 churches to kids.
"We have children that are out here shooting at night," said Turner. "We don't need them to be involved, perpetrators or victims of crime, during the day.
Pastor Turner had a message for both sides.
"I know you all have your interests, your special interests, but at the end of the day it ought to be about our children," he said.