The teachers plan to go on strike Tuesday, August 26, the Naperville Unit Education Association said.
"We have always said a strike is our last resort. However, after months of bargaining, overwhelming community support and the board's refusal to make meaningful progress, we have reached a point where we may have no other choice. As a result, we have set our official strike date," a statement from NUEA President Ross Berkley read in part.
Contract negotiations with a federal mediator resumed Tuesday.
The district says it's fully committed to reaching a fair, fiscally responsible solution that focuses on keeping students in school.
"Our top priority remains our students and keeping them in classrooms," said Charles Cush, President of the Board of Education. "We are committed to moving forward together. The strength of our district has always come from the unity between our educators and our community, and we are dedicated to preserving that."
The next federally-mediated negotiating session is set for Friday.
Educators rallied outside Naperville Central High School Monday ahead of a District 203 School Board meeting.
SEE ALSO | Naperville Community Unit District 203 students return to school as possible teacher strike looms
The district and union have been bargaining since February.
Last week, teachers voted to authorize the ability to strike.
What continues to be debated by the union and district are teacher compensation and proposed school day change.