LOS ANGELES (CBSLA) — As powerful rains pummeled the Southland Monday, thousands of Los Angeles Unified School District teachers weren’t in their classrooms – instead they were outside, picketing with parents and students in the first teacher strike in 30 years.

UTLA holds a news conference on the first day of the LAUSD teachers’ strike. Jan. 14, 2018. (CBS2)

In the first walkout since 1989, the 30,000 teachers represented by United Teachers of Los Angeles went on strike after 21 months of failed negotiations. The strike impacts 480,000 students served by LAUSD, the second largest school district in the nation.

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Classes at all LAUSD schools began at 8 a.m. as usual with substitutes, but picketing started at 7:30 a.m. State preschool sites, however, were closed and early education centers were open only for students with special needs.

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“Some schools are well-attended, some schools are less well-attended,” LAUSD Superintendent Austin Beutner told reporters at a news conference Monday regarding student attendance.

LAPD provided extra security to hundreds of elementary schools, Mayor Eric Garcetti said at a news conference Monday.

“LAPD took resources that usually are on desks — these are folks that are out on the field working as detectives — and we covered 369 elementary schools throughout the city of L.A. and L.A.’s jurisdiction.”

“So we’re going to have a normal day at school,” Beutner had told CBS2 earlier this morning. Children will “be fed, they’ll be greeted by the same principal that greets them every morning at the door, and they will be learning.”

Thousands of teachers and their supporters march in the rain through downtown L.A. on Jan.14, 2019. (Getty Images)

Thousands of teachers, students and their supporters braved the rain to rally in downtown L.A., with thousands more holding protests outside district headquarters in Sun Valley. Garcetti said an estimated 20,000 teachers took part in the protest outside city hall. All the protests were peaceful, with no word of any violence or arrests.

“This is the time to make an agreement, there is not much that separates the two sides,” Garcetti said.

At a separate morning news conference, UTLA President Alex Caputo-Pearl addressed fellow union members, parents and students at John Marshall High School.

“Here we are on a rainy day in the richest country in the world, in the richest state in the country, in a state that’s blue as it can be — and in a city rife with millionaires — where teachers have to go on strike to get the basics for our students,” Caputo-Pearl said.

The district hired 400 substitute teachers and sent 2,000 credentialed administrators back into the classroom during the strike. The district also controversially loosed background requirements for parent volunteers.

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LAUSD officials reported Monday night that more than 141,630 students attended school at campuses that normally serve nearly a half-million students. District officials said that figure did not include 54 schools that had not yet reported attendance figures as of late Monday.

Last week, California Gov. Gavin Newsom released a 2019-20 budget proposal which he said emphasized education by including a record $80.7 billion in funding for K-12 and community college, an increase of about $2 billion from the $78.4 billion in funding for 2018-19 year. After flying up to Sacramento Thursday to meet with state officials, Beutner then revised the district’s offer to the union Friday. It included a roughly $24 million increase from the previous offer, with $10 million expected to come from the county and the rest anticipated through the state budget process, Beutner said. However, the deal was rejected.

Newsom issued the following statement Monday morning regarding the strike:

This impasse is disrupting the lives of too many kids and their families. I strongly urge all parties to go back to the negotiating table and find an immediate path forward that puts kids back into classrooms and provides parents certainty.  Last week, I submitted a budget to the Legislature that would make the largest ever investment in K through 12 education and help pay down billions in school district pension debt. These historic investments will provide new resources for school districts like LAUSD, and it’s my hope this funding can help bring each side closer to a deal. ​

Beutner, a former investment banker and Los Angeles Times publisher who was named superintendent of LAUSD in May, says the district is unable to meet UTLA’s demands because there are limits on what the district can afford to do.

“Well, we’ve tried. We’ve said repeatedly we want to do everything we can to keep school open,” he said. “We want many of the same things, we want to reduce class sizes, we want to make sure we have more counselors, nurses, and librarians in schools.”

UTLA’s demands include a 6.5 percent raise that would take effect all at once and a year sooner, “fully staffed” schools with more nurses, librarians and counselors added to the payrolls, along with pledges to reduce class sizes. Negotiations have also hinged on the debate between public schools and privatizing schools through charters. The union wants to ensure that privatization doesn’t cut public school funding.

Another disagreement between the two sides is over a reported $1.8 billion district reserve. UTLA argues that the reserve could be tapped to pay for its demands, while Beutner has said the reserve has already been fully earmarked, including for the potential raises for teachers. He has argued the UTLA demands would push the district into insolvency.

“I hope UTLA comes back to the table because we have to bargain, we have to finish the contract negotiations, that’s how it gets resolved,” Beutner said.

Even as former L.A. Mayor Antonio Villaraigosa says he believes the strike is “wrong,” Los Angeles County Board of Supervisors Chairwoman Janice Hahn says she will picket today with striking UTLA members at Dodson Middle School in Rancho Palos Verdes, while LA City Councilman Joe Buscaino says he will also walk the picket line at Dana Middle School, where his daughter attends and his sister teaches. A UTLA news conference is scheduled at John Marshall High School, 3939 Tracy St., for when picketing starts, and the union also plans a rally and march at 10:30 a.m. starting at Grand Park on Spring Street in front of City Hall, heading downtown to LAUSD headquarters, 333 South Beaudry Ave.

UTLA had originally planned to start the strike last Thursday, but announced that it was pushing back the strike to Monday over a dispute regarding whether it had provided LAUSD with the legally-required 10-day strike notice.

The District has established an information hotline for parents at 213-443-1300 to answer questions about the strike. The city of L.A. has established a website, describing city resources available to students and parents during a strike.

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(© Copyright 2018 CBS Broadcasting Inc. All Rights Reserved. City News Service contributed to this report.)