(NewsNation) — The second-largest school district in the country could be on the brink of grinding to a halt.

Thousands of Los Angeles Unified School District workers are threatening to strike starting Tuesday. Teachers, cafeteria workers and bus drivers are among the employees prepared to walk the picket lines.

With a series of webinars, the district is working to inform parents of contingency plans during the anticipated three-day strike. It includes kids getting three days worth of homework when they leave Monday.

Parents are preparing, too.

“When I do have something to do, I will have one of my family members kinda just step in and help out with the kids,” parent Tomeise Ray said.

Driving the situation is Service Employees International United Local 99, or SEIU, which represents 30,000 bus drivers, custodians and other support workers who have been without a contract since June 2020.

In a show of force last week, members announced their three-day strike plan, which has the support of the powerful teachers union. The coordinated walkout of about 60,000 workers would force a systemwide shutdown.

The Los Angeles Times reports that school district leaders and the union were engaging in last-ditch negotiations Monday afternoon to avert a strike. A news conference is scheduled for 7 p.m. ET, though it was unclear officials would report progress in negotiations or announce continued preparations for a walkout.

Among other goals, SEIU is seeking a 30% pay raise. The district is currently offering about 15%, plus a bonus.

Bus drivers make an average of less than $32,000 a year, and many instructional aides are making far less than that.

“When the average pay is $25,000, one out of three SEI workers are near homelessness,” said Joel Vaca, a community school coordinator. “It’s just uncalled for.”

Throughout the nation, the shortfall in school bus drivers and support staff is severe, and it’s layered onto a significant teacher shortage.

Another layer is rampant behavioral issues and learning deficits from the pandemic.

According to Pedro Noguera, University of Southern California’s School of Education dean, it’s a lose-lose situation.

“I’m not sure what a strike will accomplish,” he said. “This is not a good thing for children, for families. At the same time, the workers have a legitimate case to make that they’re underpaid. And I think the district knows that. However, the district is in a tough bind because they don’t have the resources.”

Los Angeles Mayor Karen Bass says she is monitoring the situation and engaged with all involved parties.