Thousands of Los Angeles public school employees are poised to go on a three-day strike next week amid stalled union negotiations.

       SEIU Local 99 -- which represents approximately 30,000 cafeteria workers, bus drivers, custodians, special education assistants and other employees in the Los Angeles Unified School District -- announced on Wednesday it will lead a three-day strike from March 21 through March 23 to "protest the school district's unfair practices."

       United Teachers of Los Angeles and SEIU 99 members hold a joint rally at Grand Park in front of City Hall in a show of solidarity, Mar. 15, 2023, in Los Angeles.

       Francine Orr/Los Angeles Times via Getty Imag

       United Teachers Los Angeles, which represents more than 30,000 teachers at LAUSD, has also announced it will honor the strike and not cross the picket lines -- which could mean no classroom instruction, school officials said.

       Workers have been in contract negotiations with LAUSD for nearly a year, according to SEIU Local 99, which has been seeking wage increases, increased staffing for student services and more full-time work. Last month, 96% of its members voted to authorize a strike over the district's alleged harassment and threats against those engaging in union activities, it said.

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       "As LAUSD parents and workers, SEIU Local 99 members know a strike will be a sacrifice but the school district has pushed workers to take this action," Max Arias, SEIU Local 99's executive director, said in a statement. "Families have been sacrificing for far too long on poverty wages. Students have been sacrificing for too long in school environments that are not clean, safe or supportive for all. Too many workers have been subjected to harassment simply for demanding change."

       The average yearly salary of LAUSD school workers is $25,000, with most working part-time hours, "making it difficult to retain and recruit sufficient staff for student services," according to the union.

       United Teachers of Los Angeles and SEIU 99 members hold a joint rally at Grand Park in a show of solidarity, Mar. 15, 2023, in Los Angeles.

       Francine Orr/Los Angeles Times via Getty Images

       The district -- the second-largest in the country -- said it has offered the union a 5% wage increase and 4% one-time bonus for the current school year, as well as a 5% wage increase and a 5% one-time bonus for 2023-2024, for all bargaining unit members, as well as pay increases for some workers. The district said it has also "proposed class size reductions in all schools with further reductions and increased staffing in our highest needs schools."

       LAUSD Superintendent Alberto Carvalho charged in a statement Wednesday that the union is "simply refusing to negotiate."

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       "With a historic offer on the table that was created in direct response to SEIU's demands, and with additional resources still to be negotiated, it is deeply surprising and disappointing that there is an unwillingness to do so," Carvalho said in a statement.

       Carvalho also apologized to families and students and said they are "doing everything possible to avoid a strike."

       The next negotiation session is Friday, the district said.