The nation's second-largest school district is on the verge of chaos.

United Teachers Los Angeles – 34,000 educators strong in the schools in question – went on strike Monday as UTLA and the Los Angeles Unified School District have been negotiating a new contract for almost two years with little to show for it.

Teachers picketed their individual schools early Monday and then headed to a rally downtown. Here's what we know about the situation.

Q: Just how big is this strike?

A: LA Unified School District, which covers 710 square miles and is home to 4.8 million residents, serves more than 640,000 K-12 students. (That's more students than the entire state of Wyoming has people.) Some of those students are in charter schools, but nearly half a million are in schools where educators plan to walk out.

LAUSD is the second-largest employer in Los Angeles County. That means this strike will impact hundreds of thousands of people.

The strike comes nearly a year after West Virginia teachers walked out, kicking off a wave of teacher protests across the country. The statewide strike in West Virginia may have been historic, but it was tiny compared with the effort in LA.

Q: Why are teachers striking?

A: Teachers in LA, like those across the country, want bigger paychecks. But their demands go beyond salary increases: UTLA wants more money for counselors, nurses and librarians, plus a reduction in standardized testing and promises of smaller class sizes.

Some teachers have classes with more than 40 students in them.

Another issue for the union: charter schools, which it says take money away from neighborhood schools. Charters have exploded in California, and UTLA wants regulations on charter-school growth.

UTLA points to nearly $2 billion in reserves at LA Unified that the union says can be used immediately to pay for its varying demands.

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Q: Why won’t the district give them what they want?

A: LA Unified Schools, led by Superintendent Austin Beutner, offered teachers a 6 percent raise by the second year of a three-year contract. (The union wanted 6.5 percent, plus a year retroactive.)

The district says the nearly $2 billion in reserves is already pledged to a variety of causes, including raises for cafeteria workers and bus drivers. If it met every UTLA demand, the district says, it would go bankrupt – which isn’t just bad business, but illegal.

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Q: What will happen to the kids?

A: The district plans to keep schools open during the strike.

About 400 substitutes, plus 2,000 credentialed district staff – including administrators who used to be classroom teachers – will help fill the void of the 34,000 striking teachers.

Roughly 80 percent of students in the district rely on their school for lunch, and the schools' administrators want to make sure those students are able to eat. The schools also are committed to providing meals and a safe environment for their more than 20,000 homeless students.

The district has told parents that students will still have instructional hours, but many believe students will be stuck in auditoriums or gyms and made to do worksheets or similar exercises to pass the time.

Q: How are parents responding?

A: Many parents support the union but plan to send their children to school because they have no other choice. They work and have no child-care options during school hours.

Other parents have said they’ll hold their kids out of school and not let them cross the picket line. Some parents have even volunteered their homes as a rest stop of sorts for picketing teachers. The district has said that because school is open, students are expected to attend.

Parents Supporting Teachers, a Facebook group started by parents who have decried a lack of money for schools, had nearly 12,000 members as of Saturday afternoon.

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Q: How long might the strike last?

A: It's unclear. By hiring subs, the district has prepared for a strike that could last multiple days. But it's tough to know how long parents will put up with a potentially dramatically altered school day, or how many kids will even show up for classes.

The last teacher strike in LA, in 1989, lasted nine days. West Virginia's teacher strike in February lasted 10 days.

Q: Who’s going to win?

A. Again, it's tough to say. California is union-friendly, which would seem to give the teachers a clear advantage. Politicians in Sacramento, the state capital, typically don’t make moves unless they have the support of unions.

But LAUSD serves primarily low-income families, who might not be able to keep their kids at home or spare time away from work to picket with teachers. How those parents respond to the strike will determine whether the teachers or district has the upper hand.

Q: Aren’t teachers striking all over the country these days? Why is this walkout different?

A: Teachers have been picketing across America, dating back to last February. There have been walkouts and demonstrations in West Virginia, Arizona, Oklahoma, North Carolina, Kentucky, Colorado and Washington state.

But in most cases, those walkouts didn't happen in major urban areas. The LA strike will disrupt daily life in the country's second-most-populous metropolitan area.

LA is also different because teachers are pressuring the district for more money, as opposed to fighting the state Legislature, which happened in states such as Oklahoma.

Other unions around California are paying close attention to Los Angeles, including Oakland, where teachers could strike later this month.