The Chicago Teachers Union agreed to compromise on two key issues on Saturday and urged Chicago Mayor Lori Lightfoot to "do the right thing" ahead of its strike date on Thursday.
The strike would affect more than 360,000 students.
The teachers union would accept a phased approach to capping class sizes as well as increasing the number of social workers, case managers and school nurses, they told reporters Saturday afternoon according to the Chicago Tribune.
The union still demands Chicago Public Schools to agree to specific staff numbers, however. The two parties will return to bargaining Monday.
Lightfoot and Chicago Public Schools CEO Janice Jackson said in a statement that they "were pleased to see more progress at the negotiating table than at any time up to this point," acording to the Chicago Tribune.
Union president Jesse Sharkey called Saturday's negotiations "positive and encouraging," compared to the union's language on Friday about Chicago's counteroffer, characterizing it as "half-baked and wholly deficient" according to the Chicago Tribune.
The potential strike comes after Democratic Illinois Gov. J.B. Pritzker signed a bill in August that raises teachers' minimum salary to $40,000.