PUEBLO — A sea of teachers and their supporters descended on their district’s administration building Monday afternoon, a wave circling around the block while chanting and holding signs.

Pueblo teachers stayed out of school on Monday, launching the first teachers’ strike in Colorado in nearly a quarter-century, as they urged Pueblo City Schools District 60 leaders to agree to a 2 percent pay increase and better benefits.

Teachers from schools across the city said they don’t want the strike to last forever. But they’ll stick it out until the district agrees to the raise recommended by a third-party fact-finder.

“I got into teaching because I understand its value to society,” East High School teacher Michael Lonsberry said. “You can’t have a solid chance at a successful, productive and satisfying life without education.”

Teachers carried signs and chanted “Pueblo schools are under attack. What do we do? Stand up. Fight back,” and “Get up, get down, Pueblo is a union town!” Earlier in the day, pink from the shirts teachers wore dotted the city as groups stood outside of closed schools, next to busy intersections and in front of at least one library.

Meanwhile, school parking lots sat mostly empty. The district closed all schools Monday. Leaders are looking to see which schools they’ll be able to open as the week progresses. The district sent out a letter apologizing to families, saying it was “disappointed” in the situation.

“We’re not trying to be malicious,” said Goodnight Elementary art teacher Donna Gonzales. “We’re not trying to stop graduation. We’re not trying to mess with kids’ grades.”

Negotiations with the district have been going on for a long time, she said. The strike is happening at this point in the year because of all the steps the state requires the teachers’ union and district go through when negotiating contracts.

The tension between the union and district has been growing for years, nearly leading to strikes in the past.

The district’s teachers were paid an average of $47,617 during the 2017-18 school year, according to the Colorado Department of Education. The average Colorado teacher was paid $52,728. The National Education Association’s 2018 report said the average pay nationwide in 2017 was $59,660.

An outside fact-finder recommended that teachers and paraprofessionals get the 2 percent cost-of-living bump, determining that the district had the money. But district officials voted against the pay increase, arguing that the funds weren’t there.

District spokesman Dalton Sprouse said that the fact-finder cited the district’s reserve funds — not general funds — when determining that D60 could afford the pay increase. He said the district has previously paid teachers from reserve funds, but it’s not practical to use that money for a recurring cost.

The district said a 2 percent increase for teachers would cost roughly $1.2 million annually. The district had a $3.6 million deficit this year. Additionally, the district needs $173 million next year for building renovations and repairs to aging infrastructure.

The state teachers’ union said Colorado underfunds its schools by $822 million annually. The Pueblo district has been shorted $150 million from the state over the past eight years. When teachers raise concerns about pay, local lawmakers typically point them back to their individual districts, which determine how they allocate their funding.

District 60 expects to be in a better position next year when it goes down to a four-day school week and receives additional funding from the state. But it still won’t have a giant financial cushion, according to a letter from Superintendent Charlotte Macaluso.

“As our enrollment continues to decline, the board will have to make more difficult decisions about funding, including potential reductions in workforce and school closures,” she wrote.

The district last week gave the union two offers. Both were rejected.

Sprouse said the last offer is the best the district can do. It would have given teachers a one-time stipend equal to 2 percent of their salary, essentially $1,000 each. A 2.25 percent cost-of-living raise and an additional $50 per month towards health insurance would start in September.

But the union is looking for a retroactive 2 percent cost-of-living adjustment for the 2017-18 school year.

People are signing a pink car that calls for respect pic.twitter.com/A2Pz6w1twu — Danika Worthington (@Dani_Worth) May 7, 2018

At the intersection of Troy & HWY 50, teachers are holding signs that read “Respect! Teachers are everyone’s future” and “Fund your future.” They’ve been chanting “Pueblo schools are under attack. What do we do? Stand up. Fight back” and “Get up, get down, Pueblo is a union town” pic.twitter.com/ywt3QoP73O — Danika Worthington (@Dani_Worth) May 7, 2018

“Our district has disrespected us for too long,” East High School teacher Julie Cain said. “We are having a really hard time getting and keeping good teachers.”

Cain, who has been working in District 60 for 24 years, said the district loses teachers to Colorado Springs, Cañon City and Pueblo’s District 70.

The Pueblo district has 30 schools serving roughly 16,000 students, according to its website. There were 992 teachers in the 2017-18 school year, according to the state education department. The district has an 18 percent teacher turnover rate.

The community has been largely supportive, Cain said. Firefighters dropped off food and water. Parents brought burritos and Gatorade. As Cain said this, a woman slowed down while honking in support. She leaned out of the window, giving the group a thumbs up. “Go teachers!” she said.

The last teacher strike in Colorado occurred in 1994. Denver teachers walked off the job for five days. Then-Gov. Roy Romer helped end the strike.

Pueblo teachers nearly held a strike in 1998, but state regulators mediated a resolution. The Colorado Department of Labor and Employment last week declined to intervene in the current dispute.

Teachers are quite literally on streets all over the city. Meanwhile, I’ve passed schools with only a handful of cars in the parking lots pic.twitter.com/24mn2shclN — Danika Worthington (@Dani_Worth) May 7, 2018