(CNN)Thousands of Washington state students missed their first day of class Thursday, and it's not clear when they'll be able to start their school year.
6,000 Washington teachers go on strike, causing kids to miss their first day of school
Superintendents and school boards are at odds with school employees over pay rates, the Washington Education Association said.
Nearly 6,000 teachers are on strike in nine western Washington school districts that were supposed to start class Thursday.
The largest of those nine districts is Tacoma Public Schools, with 30,000 children and about 5,000 employees.
Last week, the state's largest school district -- Seattle Public Schools -- averted a massive teachers' strike after the Seattle Education Association and the school district reached a tentative deal Friday, the district and the teacher's union said.
The Seattle district did not make the terms of the agreement public.