Tens of thousands of teachers in Arizona and Colorado walked out of public school classrooms on Thursday to demand better pay and more education funding, in the latest revolt by educators that has spread to the U.S. West.

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At least 50,000 teachers and their supporters wearing red T-shirts streamed down city streets in Arizona's capital of Phoenix, carrying placards reading '35 is a Speed Limit NOT a Class Size' and 'The Future of Arizona is in my Classroom.' 

The teachers are demanding an immediate 20 percent increase to salaries which are among the lowest in the country; increased pay for support staff; restoring education funding to 2008 levels, and a freeze on tax cuts until the state's education budget reaches the national average.

Arizona Governor Doug Ducey, a Republican, has offered a cumulative 20 percent pay rise by 2020 to be largely paid for by growth. He says the state needs low taxes to attract employers, and has pledged US$371 million over the next five years for school infrastructure, curriculum, school buses and technology.

"We've all been listening, but now it's time to act," Ducey said in a statement, as he pushed lawmakers to fund his plan. "My No. 1 focus right now is passing a 20 percent pay raise for Arizona teachers. This raise is earned, and it is deserved."    

Teachers say the governor's budget promises are too optimistic and a deal with lawmakers could be years in the offing.

Encouraged by similar protests in West Virginia, Oklahoma and Kentucky, organizers said the job action would send a message to state political leaders about their dissatisfaction.

Colorado public school teachers announced a two-day walkout for Thursday and Friday and around 3,000 people marched on the state capitol in Denver to demand additional funding, according to protest organizers.

The vast number of Arizona's more than 200 public school districts with roughly 1.1 million students have canceled classes for Thursday and Friday.

"Today will forever be remembered as the day that Arizona educators, after decades of being ignored, stood up and said ENOUGH," tweeted Noah Karvelis, a music teacher and leader of the grassroots Arizona Educators United, a coalition of teachers and education professionals. 

By early afternoon, rally organizers adjourned the event as a precaution due to high temperatures.  

Teachers' Pay Movement

Arizona state schools superintendent Diane Douglas has asked the teachers not to leave their classrooms and allow state leaders to work out a solution. She feared the job action would only hurt students and parents.

One critic of the walkouts said it sets a bad precedent for other public service groups, such as police and firemen, and that a better solution is to redirect money from school administration to teachers.

"Before demanding more of Arizonans' meager paychecks, our education community should reallocate the dollars they already spend," wrote Jon Gabriel, a Mesa resident and editor-in-chief of Ricochet.com, a conservative discussion forum. 

The protests in Colorado, where Republicans control the senate but Democrats hold the governor's office and control the lower house, marked a political shift for the teachers' pay movement. Until now, demonstrations have been limited to Republican-controlled states where public sector unions are weak.

The Colorado walkout forced the state's two largest school districts, in Denver and neighboring Jefferson County, to cancel classes. The teachers' union said it expected between 10,000 and 15,000 teachers to descend on the capitol over the two days.

"We welcome teachers to the State Capitol! We are listening – let's work on this together," Colorado Governor John Hickenlooper tweeted.

Colorado is enjoying an economic boom, but teachers say they have to work second jobs and buy school supplies out of their own pockets after a US$6.6 billion cut in funding over the past decade.

Low pay means the state is short 3,000 teachers, according to Kerrie Dallman, head of the Colorado Education Association, a statewide federation of teachers' unions.

"School districts and public school supporters end up begging for the leftover money at the end of every legislative session," said Dallman, whose group organized the march on the capitol.