It is Arizona's first statewide strike. Teachers at first conducted a "walk-in," wearing Red for Ed T-shirts and buttons and waving similar signs at before-school protests, before getting on and teaching their students. The strike began on April 26, a Thursday, and continued the following day, a Friday.

Many schools have already announced that they are closing their doors on Monday, as the strike continues. The teachers are rallying to call for more money for education and for their own salaries. American Federation of Teachers President Randi Weingarten will be in Phoenix to speak at a rally at the statehouse.

Churches and community centers are among the public buildings being tapped to house children who would otherwise be in school. Across the state, day camps have sprung up as well.

Schoolchildren usually each lunch at school, and so those looking after those not in school have gathered food from friends, family, and community organizations. Also collected have been donations for schools' hourly staff who are not salaried teachers and who would otherwise be at work.

In Phoenix, the crowd numbered in the tens of thousands, with teachers calling for a 20 percent raise in their own pay, an increase in pay for support staff, and about $1 billion more in education funding. Arizona teacher average salary is well below the national average.

The state's governor, Doug Ducey, has set out a plan for meeting the teachers' demands, but protest organizers say that the revenue projections needed to offset the salary increase (which included no increases in taxes) were too optimistic.

The Arizona Education Association said that it had no end date in mind for the teacher walkout; more than 840,000 students in more than 100 districts across the state did not go to school. The state's Department of Education said that the schoolchildren population was more than 1.1 million.

Similar efforts took place in other recent states in which teachers protested in large numbers. Those states were Kentucky, Oklahoma, and West Virginia.

Teachers in Colorado have walked out of school in similar protests. Many schools in that state were also closed Thursday and Friday.