(CHICAGO) The spotlight is on contract talks between teachers and officials with the nation’s third-largest school district as Chicago students attend the first day of school.

Chicago Public Schools CEO Forrest Claypool and Chicago Teachers Union President Karen Lewis both held public appearances Tuesday. The question of whether there could be a strike this fall lingers.

The contract for about 27,000 union members expired in June 2015.

The two sides have been negotiating on issues including cost-of-living raises, pensions and other benefits. Earlier this year, the union’s bargaining team rejected a district proposal.

Lewis declined Tuesday to discuss the latest status. She says union members are meeting this week and could consider a strike authorization vote.

School district officials say the earlier agreement rejected by the union is a “fair foundation.”

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