California Sen. Kamala Harris, a Democratic presidential candidate, unveiled a $315 billion plan Tuesday to give public school teachers across the country an average $13,500 raise — a plan her campaign is calling “the largest federal investment in teacher pay in the country’s history.”

“The people who are going to educate our children are our teachers, and for too long, they have been paid substandard wages,” Harris said in an interview on CBS News Tuesday morning. “Let’s pay them their value.”

The plan, which would cost an estimated $315 billion over 10 years, aims to close the “teacher pay gap” identified by the left-leaning Economic Policy Institute, which found that teachers made 11.1% less than comparable workers in other professions in 2017, even with benefits factored in.