The strike comes after teachers and the district failed to reach an agreement over higher wages, health benefits, and more resources for special needs students. The San Francisco Unified School District closed all its 120 schools and said it would offer independent study to some of the district’s 50,000 students.

“We are facing an affordability crisis,” Cassondra Curiel, president of the United Educators of San Francisco, said in a statement Sunday night. “Family healthcare premiums of $1,500 per month are pushing excellent teachers and support staff out of our district. This week, we said enough is enough.”

Teachers with the union were joining the picket line after last-ditch negotiations over the weekend failed to reach a new contract. Mayor Daniel Lurie and Democratic U.S. Rep. Nancy Pelosi of San Francisco had urged the two sides to keep talking rather than shut down schools.

Union leaders planned to hold a news conference Monday morning about the strike and an afternoon rally was planned at San Francisco City Hall. Negotiations were scheduled to resume midday Monday.

The union and the district have been negotiating for nearly a year, with teachers demanding fully funded family health care, salary raises and the filling of vacant positions impacting special education and services.

The teachers also want the district to enact policies to support homeless and immigrant students and families.

The union is asking for a 9% raise over two years, which would mean an additional $92 million per year for the district. They say that money could come from reserve funds that could be directed back to classrooms and school sites.

SFUSD, which faces a $100 million deficit and is under state oversight because of a long-standing financial crisis, rejected the idea. Officials countered with a 6% wage increase paid over three years. On Friday, San Francisco Unified School District Superintendent Maria Su also said the offer also includes bonuses for all employees if there is a surplus by the 2027-28 school year.

A report by a neutral fact-finding panel released last week recommended a compromise of a 6% increase over two years, largely siding with the district’s arguments that it is financially constrained.

The union said San Francisco teachers receive some of the lowest contributions to their health care costs in the Bay Area, pushing many to leave. Su said the district offered two options: the district paying 75% of family health coverage at Kaiser or offering an annual allowance of $24,000 for teachers to choose their health care plan.

Lurie, who helped broker an agreement that ended a hotel workers unions strike after he was elected and before taking office, said that the city agencies were coordinating with the district on how to offer support to children and their families.

“I know everyone participating in these negotiations is committed to schools where students thrive and our educators feel truly supported, and I will continue working to ensure that,” Lurie said in a social media post Sunday.