More than 60,000 bus drivers, custodians, cafeteria employees, campus security, teaching assistants and educators from the Los Angeles Unified School District say they’ll strike from March 21 to 23, a move likely to shut down hundreds of schools. 

The labor unions representing the support staff announced the dates during a lively rally on Wednesday afternoon at Grand Park in downtown Los Angeles. 

Represented by labor union SEIU Local 99, about 30,000 school support staff are demanding LAUSD pay for a 30% raise and $2 per hour equity wage increase. About 35,000 teachers represented by the United Teachers of Los Angeles plan to join them. The school district has offered, in part, more than a 15% raise, retention bonuses and to bring its minimum wage up to $20.

In a letter to families on Monday evening, Superintendent Alberto Carvalho told parents the district is trying to work with the union to come to an agreement before kids are severely impacted by the closures. And he and district negotiators are prepared to work around the clock to come to negotiations before the strike, he told news reporters on Wednesday morning.

“We are committed to continue good faith bargaining with our labor partners around the clock to reach an agreement before a strike occurs. I have invited union leaders to have a direct conversation with me to negotiate day and night to reach an understanding to spare our children from the avoidable disastrous consequences of a strike. Our students should not be victims,” his letter reads. 

In an interview with USA TODAY on Tuesday, Local 99 Executive Director Max Arias said he doesn’t see the district budging and in turn doesn’t anticipate a compromise before the planned protest.

He said education workers will continue to “bargain to improve the conditions of schools and the people who work there” until the district meets their demands. Many of the district’s support staff are living below or near the poverty line due to low wages or the limited hours of work the district currently offers them, he said.