Bargaining units at most of the state's 295 school systems have sought to renegotiate salaries this year after the state infused $1 billion for teacher pay to resolve a long-running court battle that determined the state was inadequately funding public education.

Tacoma Public Schools has said it has been treated unfairly in the state's new funding formula and doesn't have a windfall of cash to give away like some other districts.

The Tacoma district said it hopes an independent third-party can confirm its financial condition so contract talks with teachers can move forward.

Union leaders have decried the district's move as a "novel way" to avoid good-faith bargaining by using an arbitrator to prolong the process that could keep teachers and students out of school.

As students across the state return for a new school year, teachers in at least 18 districts have voted to authorize strikes, gone on strike or settled negotiations over pay raises.

Teachers in the Seattle, Tukwila, Stanwood-Camano, Washougal and other districts have won higher salaries.

Last week, judges in Tumwater and Longview ruled against teacher unions for striking and urged them to go back to school and the bargaining table. However, no penalties were imposed.

Tumwater remains on strike, while Longview reached an agreement over the weekend.

Centralia teachers also remain on strike.

-- The Associated Press