LOS ANGELES – As he crossed the picket line and started toward the front doors of Colfax Charter Elementary in North Hollywood, a young boy wearing a backpack turned around and took in the sight before him.

“What’s going on?” he asked softly, as a puzzled look crossed his face.

“No teachers, no school,” another student said, pointing to the demonstration.

Thirty feet away, on the sidewalks and in a driving rain, teachers marched, held signs and chanted. They went on strike Monday, along with about 34,000 of their colleagues at Los Angeles Unified Schools, the nation's second-largest district.

“Education is a right! That is why we have to fight!” they shouted. “Hey hey! Ho ho! We’re fighting to keep class size low!”

They took photos of signs and passed out red ponchos, donning the color that has become synonymous with the teachers' labor movement.

The wave of teacher strikes that has rocked education for the past 11 months culminated Monday in the L.A. walkout. The union plans to continue picketing Tuesday.

Los Angeles Unified, where the strike affects half a million students at more than 900 schools, opted to keep its doors open this week as teachers protest outside. The educators are rallying for better pay, smaller classes, fewer standardized tests, charter school regulation and more counselors, librarians and nurses.

As she crossed the picket line, an art instructor at Colfax – whose job is not covered by the union contract – wiped away tears.

“I’d like to know what (President Donald) Trump thinks of this,” said Joanna Bellson, who has two children in the district. Her daughter's first-grade class has 37 students. One of her son's sixth-grade classes has 50. “This is the real crisis, not the (border) wall.”

'No homework!'

After they picketed their individual schools early Monday, teachers from across L.A. County flooded Metro transit trains and headed downtown to City Hall. There, they rallied and marched a mile uptown to the district office, calling for Superintendent Austin Beutner to resign.

“Hopefully, he realizes he’s in a losing battle,” said Ly Hua, a 15-year teacher working at Bravo Medical Magnet.

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Most students in the district come from low-income families, and some parents aren't clued into the strike or can't afford to find backup child care for their children. The district promised to supervise children, using about 400 substitutes and administrators who are former teachers.

Students who attended school played educational games on iPads and did worksheets. Southern California schools are designed to accommodate large groups in the school yard, but that wasn't an option with Monday's rain. So students were crammed into auditoriums and cafeterias in some schools.

At Colfax Charter, about 60 children – roughly 10 percent of the usual enrollment – entered the school despite the protests and were directed into the auditorium. Many of them wore red.

A short while later, a few parents walked back into the school and emerged with their children. They weren't OK with the auditorium setup, they said.

Dania Castillo, 10, a fifth grader, attended school Monday at Marianna Avenue Elementary. She had expected to sit and watch movies all day, and she did watch some videos. But she read in the library and worked on math questions and writing exercises, too.

“It’s gonna be really fun because we get no homework!” said Bridget Castillo, 10, a Marianna Avenue fourth grader. Usually, she said, she gets six worksheets to take home. She only got one on Monday, but students were told they "didn't really have to do it."

The district said principals on Monday reported 141,631 students attended 1,240 schools, including 216 independent charters that are not being affected by the strike. The charter schools' combined enrollment is 117,331, according to the district, so the charters likely accounted for much of Monday's attendance.

California sends schools money according to daily attendance figures, so the absences cost the school $15 million Monday. That figure accounts for money the district saved by not paying the salaries of striking teachers.

Beutner declined to say how long the district could sustain those losses.

Students received meals at all schools, the district said, and buses transported 40 percent of their normal riders.

46 students in one class

At John Marshall High School in the city’s Los Feliz district, a throng of about 50 teachers toting umbrellas and picket signs gathered early Monday morning outside the main entrance.

For Marshall education teacher Mike Finn, the top issue is class size. He said having 46 students in one composition class is unmanageable.

When it comes to preparing students for college, he said, “Everybody’s talking class size.”

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Los Angeles teachers have not gone on strike since 1989. That walkout lasted nine days.

Scott Mandel, a teacher with 34 years in the school district, was teaching sixth grade during the ’89 strike. Last week, he wrote an open letter to his fellow teachers, trying to buoy spirits while injecting a dose of reality.

“This isn’t just a protest on the streets, passing out flyers,” wrote Mandel, who teaches Film, Arts and Media at Pacoima Middle School. “You need to think about the ramifications of what you’re about to do. You need to think about the reasons you’re out there on the line. And you should be a little scared.”

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'Our Armageddon'

The strike comes nearly a year after West Virginia teachers walked out, kicking off the teacher protests. The statewide strike in West Virginia may have been historic, but it was tiny compared with the effort in LA. The affected LA schools have nearly twice as many students as the entire state of West Virginia.

The L.A. strike does more than carry on the momentum of teacher demonstrations across the nation. Most protests in the past year have been in suburban and rural areas, not massive urban centers with high costs of living.

L.A. schools are 90 percent students of color and 80 percent low-income students.

At Marshall High, a few of those students joined the protest rather than going inside.

“I cannot stress how important this strike is to me,” said Lola Babich, 15, a sophomore, to the crowd. “Teachers are the most important people in my life.”

With 45 kids in a classroom, she said in an interview, "It is so hard to focus.”

For Mandel and his fellow educators, “This is our Armageddon,” he said.

LAUSD left teachers with no other option but to walk out, he said.

The district offered teachers a pay raise but didn't meet many of their other demands. The schools have nearly $2 billion in reserves, which teachers want the district to spend.

Administrators said the savings are pledged to a variety of causes, including raises for cafeteria workers and bus drivers. If it met every union demand, the district said, it would go bankrupt – which isn’t just bad business, it's illegal.

"We urge them to resume bargaining with us, anytime, anywhere," Beutner said of the teachers union.

It's not that simple, Mandel said, describing the strike as "the ultimate game of chicken."

Teachers, he vowed, aren’t going to swerve first.

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Contributing: Kristin Lam and Erin Richards, USA TODAY