Thousands of teachers in Colorado and Arizona rallied for a second day on Friday to demand higher pay and school funding as a revolt by US public school teachers spread westward.

Waving placards such as "Teachers Just Want To Have Fund$," educators and their supporters descended on the state capital in Denver to demand an increase in school budgets.

In Arizona, thousands rallied in Phoenix for an immediate 20-percent increase to teacher salaries, which are among the lowest in the country, and restoring education funding to 2008 levels.

Arizona state Governor Doug Ducey announced a deal with state legislative leaders to raise teachers' pay 20 percent by 2020.