LOS ANGELES (AP) — Students in the nation’s second-largest school district could return to class next month under a tentative deal announced Tuesday with the powerful teachers union.

The Los Angeles Unified School District and the union said the tentative agreement provides a number of “safety parameters” that would allow a partial reopening of campuses.

As with most other California public schools, LAUSD’s more than 600,000 students have been learning online for almost a year because of the coronavirus pandemic.

“It’s our shared commitment to the highest safety standards and spirit of trust and collaboration we will take with us back to schools,” Superintendent Austin Beutner and United Teachers Los Angeles President Cecily Myart-Cruz said in a joint statement.

The plan, which needs ratification by the school board and the union membership, lays out a roadmap for reopening schools after Los Angeles County drops from the state’s most-restrictive COVID-19 tier, purple, into the red tier, which county officials said could happen as early as this week.

Preschool and elementary schoolers would return in mid-April. Middle and high school students would follow at the end of April.

Crucially, the agreement says teachers, along with nurses and other union members, won’t have to return to work until they have been fully vaccinated for COVID-19.

The teachers union had demanded such a requirement in refusing to accept an earlier mid-April target date. In a statement Tuesday, however, Myart-Cruz said the agreement meets “all of our key safety protocols.”

The Board of Education appeared ready to approve the agreement.

“It’s been a long tough year but this is truly the best possible outcome,” member Jackie Goldberg said.

Under the plan, preschoolers would have full-day in-person instruction, while elementary schoolers will use a hybrid model combining some time in class and the rest online. Class sessions will be staggered, with some students going in the morning and others in the afternoon to keep classes small enough to permit social distancing.

Students would still have the option of remaining entirely in distance learning.

For now, students in middle and high schools will continue learning online, although they can return to campus “for peer interaction, social-emotional learning and lessons for college and career exploration,” according to the statement.

All students and staff will have to wear masks and practice social distancing and they will be tested for COVID-19 before returning to campus and weekly thereafter, the statement said.

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