LAKE FOREST, Ill. (CBS) — Teachers at Lake Forest High School remain on strike this Friday morning, and classes are again cancelled.

But as WBBM Newsradio’s Dave Berner reports, both sides continue to talk.

LISTEN: WBBM Newsradio’s Dave Berner reports

Teachers and administrators negotiated until 9:20 p.m. Thursday. They are set to resume talks Thursday morning.

The teachers went on strike on Wednesday.

The main concerns have been salary relations and a proposed restructuring of the salary schedule.

Teachers say they accepted a pay freeze last year due to the down economy, and now they say the school board is trying to lock in those sacrifices by creating a two-tiered system of hiring in which new teachers won’t be paid at the same rate as current employees.

But opponents of the strike accuse teachers of being greedy.

About 80 Lake Forest teachers earn more than $100,000 a year, in a town with a median household income that’s about twice that. But union spokesman Chuck Gress said the new hires start at $50,000, and have much less opportunity for big pay raises.

Teachers are expected back on the picket lines at Lake Forest High School Friday morning.

Meanwhile in Highland Park, a federal mediator is leading negotiations between teachers and school board members for North Shore District 112.

Talks are set to resume Oct. 4. Teachers have been without a contract since late August, and last week, teachers gave negotiators the authority to announce a strike.

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