CHICAGO (CBS) — The Chicago Teachers Union is just three days away from going on strike if a new contract isn’t reached with the city.

Negotiations with Chicago Public Schools leadership will resume Monday morning, ahead of the union’s plan for an indoor rally and then march through the city Monday afternoon.

Meanwhile, the mayor and the CEO of Chicago Public Schools say they remain committed to getting a deal done.

Both sides met over the weekend for another round of negotiations and agreed some progress was made.

Union leaders said over the weekend it was surprisingly sober on the other side of the table, especially after the city told the union on Friday it has already issued a final contract offer, which includes a 16% total raise over a five-year contract.

The teachers union said it proposed a structure on two key concerns — class size and staffing — and came up with a pathway offer to phase them in.

The union is also pushing for more nurses, case managers, and counselors; but did make modifications to some of those proposals.

“It’s still a proposal that would provide justice for our students and for our teachers and schools, but it’s a path that she [Mayor Lightfoot] can follow in order to get a settlement, a settlement we all want,” said CTU President Jesse Sharkey.

Union leaders say the ball is now in the city’s court.

As for a contingency plan, CPS launched a website to help parents navigate in case of a possible strike.  They say CPS buildings will be open for students who need a place go during school hours.