MAYWOOD, Ill. —  Classes are canceled the rest of the week in Proviso District 209 after talks between the union and schools produced no agreement. 

Proviso Math and Science Academy, Proviso East High School and Proviso West High School will be closed Thursday, March 10 and Friday, March 11.

As a result, Local 571, the union that represents District 209 teachers, will remain on the picket lines. 

After failing to come to terms Wednesday, both sides will meet again with a federal mediator on Friday.

The union said the most significant unresolved issues are teacher pay, teacher retirement and smaller class sizes.

WGN News reported that teachers sought a 13% pay increase over a three-year contract. The district proposes a 9% pay increase over three years, keeping both sides more than $1 million apart in negotiations.

Read more Chicago News Headlines here

About 4,000 high school students are affected by the walkout.