Valley View School District includes high schools in Romeoville and Bolingbrook.
This comes after teachers set a strike date for next week.
The union had objected to plans to extend the workday by 20 minutes.
Details of the deal will not be made public until teachers have a chance to review it and to vote on the proposal.
SEE ALSO | Teachers at south suburban School District 146 file 'intent to strike' paperwork