A nationwide teachers’ revolt that last year saw walkouts in West Virginia, Oklahoma and other largely Republican-run states has now spread to California, where teachers and support staff in the vast, sprawling, predominantly low-income Los Angeles Unified School District are on the verge of striking.

About 31,000 members of the local teachers’ union are threatening to walk off the job on Monday to demand better pay, lower class sizes and improved student access to nurses, psychological counselors and other key services.

Their union, United Teachers Los Angeles, has been fighting with the school district – America’s second largest – for more than a year. Both sides agree that schools are underfunded and teachers underpaid, but that has not prevented trust between the two sides from eroding to a vanishing point.

In contrast to the disputes in Oklahoma and other red states, where the fight has been seen as one pitting teachers and administrators against tight-fisted conservative legislators, the fight in Los Angeles is, essentially, a bitter family squabble over dizzying challenges and dismally inadequate resources.

The district has proposed a 6% pay rise over the first two years of a new three-year contract. The union wants a 6.5% raise right away as well as a flurry of new hiring and other school resources.

“We are at a watershed moment in defending public education in Los Angeles,” the union told its members late last month, describing the moment as one of existential crisis.

The difference between the two sides, which shows no sign of being resolved, is likely to lead to major disruptions across the city if the threatened strike becomes a reality. The district wants students to come to school even if teachers are not there, but has hired just 400 extra support staff to take the place of 31,000 unionized workers. Nobody knows what largely unsupervised schools are going to look like, especially if the walkout stretches out over days or weeks.

Some parents have said they will keep their children home in solidarity with the striking teachers, but many others have to work and cannot afford extra childcare. More than 80% of district students are poor enough to qualify for free breakfast and lunch. If they don’t come to school for those meals, it’s unclear if they can afford to eat at all.

The crisis is piling pressure on the Los Angeles mayor, Eric Garcetti, who has no direct control over the school district but knows the optics are bad for a possible presidential bid. He has offered to act as a mediator, but the union has rebuffed his offer.

It is piling pressure, too, on California’s newly inaugurated governor, Gavin Newsom, who has ambitious plans to expand access to early-childhood education and community college but has not so far proposed a significant increase in school funding.

The district claims its hands are tied in the contract negotiations because it relies on the state for funding and revenues have been dropping over the past decade. That’s partly because of the 2008 recession but also because funding depends on enrollment and parents have been shifting their children out of struggling district schools in growing numbers.

The union, for its part, points to a $1.8bn reserve fund – a fund the district says it needs to meet a growing shortfall in pension and health benefit obligations – and fears that the district is more interested in promoting charter schools and dismembering public education than it is in making sure teachers have what they need to excel in the classroom.

One lightning rod of criticism is the district’s relatively new superintendent, Austin Beutner, a former Wall Street investment banker who has proposed breaking up the district into 32 mini-fiefdoms. UTLA describes Beutner as an “out-of-touch billionaire” and a “corporate downsizer” at odds with the core mission of public schools.

Another lightning rod is the school board, which over the past couple of election cycles has filled with ever more champions of charter schools, which now educate almost one-third of Los Angeles schoolchildren district and in some cases share space with the public schools whose students they are luring away.

All the bad blood has a long history, however, stemming in particular back to a watershed referendum in 1978 that capped California’s property taxes and slowly turned one of America’s best-funded state education systems into one of its worst. “We’ve seen a national momentum in favor of teachers … and California has a historically underfunded system,” said Robin Lake of the Center on Reinventing Public Education, a research organization based in Washington state.

In Los Angeles, the problems have only been magnified because of the city’s size and because of the large number of lower-income children who fail to graduate high school at a shocking 50% clip. Lake argued that while the district’s financial struggles are genuine, it has also managed to alienate students and parents by expanding the size of its central office and making ever more demands of its employees without providing extra resources.

“Teachers have a general sense that they are not being respected,” Lake added. “A lot of them see the push for education reform as a bit of a slap in the face.”

Most observers agree the best solution would lie in all the parties – locally and in state government – coming together and figuring out a common approach. Instead, however, Beutner’s office and UTLA are exchanging daily stink bombs in the form of press releases, public statements and – increasingly, as the prospect of a strike has drawn nearer – in dueling filings in court. The strike was, in fact, due to start on Thursday, but the district sued for a delay on a procedural technicality and won. Both sides met again for negotiations on Friday afternoon. The union rejected a new offer by the district later that day, calling it “woefully inadequate”.