LOS ANGELES — The Los Angeles board of education voted Thursday to require students 12 and older to be vaccinated against the coronavirus to attend in-person classes in the nation’s second-largest school district.

The move makes Los Angeles by far the largest of a very small number of districts with a vaccine requirement. Nearby Culver City imposed a similar policy last month for its 7,000 students.

The Los Angeles Unified School District, which has more than 600,000 mostly Latino students, already tests all students and employees every week, requires masking indoors and outdoors and has ordered employees to be vaccinated. Under the vaccination plan, students 12 and up who participate in sports and other extracurricular activities need to get their two-shot sequence completed by the end of October. Others have until Dec. 19.

“It is easy to wait for someone to tell us what to do. LA Unified is leading because we must. Our communities cannot wait,” Mónica García, a board member, said before the vote.

“This action is not about violating anybody’s rights. This action is about doing our job to be able to offer public schools that children can come to school and be safe,” she said.

Los Angeles Unified was among the last of the nation’s largest districts to reopen to classroom instruction last spring. The teachers union opposed the move for months, citing health concerns.

The district's student population is nearly three-quarters Latino and many are poor. Among adults, poor Latinos are vaccinated at a lower rate than the state average.

Los Angeles County saw an increase in coronavirus case rates in children from mid-July to mid-August but these have since declined, said Barbara Ferrer, director of the county's Department of Public Health. The shift coincided with the reopening of many schools with safety measures such as masking and testing, she said, adding that bringing so many children to school could lead to more exposures and officials will be monitoring closely.

Los Angeles school board members overwhelmingly supported the plan, calling it a sound public health measure and a critical step to keep classrooms open for the in-person learning so essential for students. Board member Jackie Goldberg recalled when polio ripped through her school and her friend in third grade lost his arm.

“It is our moral, ethical, religious, political — pick a word — it's our responsibility to protect the children under 12 who cannot get protected any other way,” she said.

There are not yet any vaccines against the coronavirus authorized for children under 12.

Under LA Unified's plan, all students age 12 and up will be fully vaccinated by the time they return to class following winter break on Jan. 11. Those who are participating in sports and other activities need to receive a first dose of vaccine by Oct. 3 and a second dose by Oct. 31, while other students need to get their first dose by Nov. 21 and a second dose no later than Dec. 19.

Some parents are eager to see all eligible students vaccinated. Lucy Rimalower, who has a kindergartener in the district, said she is relieved officials are taking steps to try to protect her son until he is old enough to get his shot, and that also helps protect her parents, who are in their 60s and 70s and help her with child care.

“This feels like following the precedent of all the other vaccines over time that have helped us to have a safer school environment, that lets us feel like it’s safe to send our kids to school without getting chickenpox, polio, the mumps, measles, rubella, you name it,” she said.

Other parents oppose the move and believe it should be up to parents, not the board, to decide what is best for their children. They noted coronavirus has been far less lethal for children than for older adults.

“We don’t understand why you are so rushed,” Diana Guillen, chair of the district’s English learner advisory committee, told the board in Spanish. “This decision should be ours, a family decision.”

United Teachers Los Angeles urged the district to provide public education and outreach to families and access to the shot to increase vaccination numbers in school communities. The teachers' union had urged the board to mandate student vaccinations once teachers were required to get the shots and applauded the move on Thursday.

So did the Los Angeles County Department of Public Health. Between Aug. 15 and Sept. 7, nearly 8,000 student cases and more than 1,200 staff cases of coronavirus were reported in the county, most of them in Los Angeles Unified, which conducts weekly testing, Ferrer said. She said that doesn't mean the infections spread through the schools, and many in fact occurred elsewhere.

She added that more than half the county’s residents between 12 and 17 are already fully vaccinated.

“Increasing these numbers is a critical part of our strategy for keeping schools open,” she said. “Widespread vaccination can dramatically reduce transmission in all settings, especially and particularly at schools.”