Hope Brown can make $60 donating plasma from her blood cells twice in one week, and a little more if she sells some of her clothes at a consignment store. It’s usually just enough to cover an electric bill or a car payment. This financial juggling is now a part of her everyday life—something she never expected almost two decades ago when she earned a master’s degree in secondary education and became a high school history teacher. Brown often works from 5 a.m. to 4 p.m. at her school in Versailles, Ky., then goes to a second job manning the metal detectors and wrangling rowdy guests at Lexington’s Rupp Arena. With her husband, she also runs a historical tour company for extra money.

“I truly love teaching,” says the 52-year-old. “But we are not paid for the work that we do.”

That has become the rallying cry of many of America’s public-school teachers, who have staged walkouts and marches on six state capitols this year. From Arizona to Oklahoma, in states blue, red and purple, teachers have risen up to demand increases in salaries, benefits and funding for public education. Their outrage has struck a chord, reviving a national debate over the role and value of teachers and the future of public education.

Hope Brown works at Rupp Arena in Lexington, KY on Aug. 31.
Hope Brown works at Rupp Arena in Lexington, KY on Aug. 31. Maddie McGarvey for TIME/Economic Hardship Reporting Project
For many teachers, this year’s uprising is decades in the making. The country’s roughly 3.2 million full-time public-school teachers (kindergarten through high school) are experiencing some of the worst wage stagnation of any profession, earning less on average, in inflation-­adjusted dollars, than they did in 1990, according to Department of Education (DOE) data.

Meanwhile, the pay gap between teachers and other comparably educated professionals is now the largest on record. In 1994, public-school teachers in the U.S. earned 1.8% less per week than comparable workers, according to the Economic Policy Institute (EPI), a left-leaning think tank. By last year, they made 18.7% less. The situation is particularly grim in states such as Oklahoma, where teachers’ inflation-adjusted salaries actually decreased by about $8,000 in the last decade, to an average of $45,245 in 2016, according to DOE data. In Arizona, teachers’ average inflation-adjusted annual wages are down $5,000.

http://time.com/longform/teaching-in-america/