12/04/2012 10:17 am ET

Community Unit School District 300 Teachers Strike, No Classes For 20,000 Illinois Students Tuesday

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About 20,000 students in suburban Chicago are going without class or after-school activities Tuesday as Community Unit School District 300 teachers moved to strike after failing to negotiate a new contract.

According to the district's website, Local Education Association of District 300 (LEAD) 300, the district's teachers' union, and the district met all day Monday and, even with the help of a federal mediator, were not able to resolve their remaining contractual issues. While the district says it has agreed to the union's call for class size reductions, salaries appear to be the sticking point.

However, union spokesman Mike Williamson told the Daily Herald that class size -- as well as salaries -- are both outstanding issues that have not yet been resolved, even after 11 months of negotiations. But, according to Patch, Williamson is confident "we are pretty close" to a resolution and union officials are hopeful the strike will end soon.

“I’m not sure they feel the same way. We’d like them to come and meet with us and quickly resolve this. Hopefully we won’t be out long," Williamson told Patch.

The Carpentersville, Ill.-area school district has more than 20,000 students and employs about 1,200 teachers spread out between 27 schools covering 118 square miles and encompassing 15 different communities and four counties, NBC Chicago notes. It is one of the state's largest school districts. The teachers' last contract expired on July 1 and the union last went on strike in 1972.

The teachers hit the picket lines at their home schools at 7 a.m. Tuesday, according to ABC Chicago.

The District 300 teacher walkout arrives on the heels of a series of other Chicago-area strikes this fall, including strikes in Highland Park, Evergreen Park, Chicago, Lake Forest and Crystal Lake districts.