Medford School District canceled Thursday classes on Wednesday afternoon, bracing for a possible teacher strike.
School Superintendent Phil Long made the announcement on the school district's web site before classes ended for the day on Wednesday.
Long's statement says negotiations with the teachers' union continue, and may continue overnight.
If the teachers do strike over pay, benefits, and working conditions, school will reopen on an altered schedule next Tuesday.
Either way, all schools will be closed Thursday.