It's a stark contrast to the current head of the department, DeVos, who for decades has supported charter schools and taxpayer-funded vouchers for private and religious schools -- a policy known as "school choice" that critics say drains support from public schools.
It's one of the reasons DeVos has become a lightning rod for the Democratic Party.
During the 2018 midterms, she was frequently used as a key symbol of privatizing education in attack ads run by Democrats who touted their support for public schools. She's now becoming a staple of the 2020 election as well.
"I'll just be blunt: Betsy DeVos is the worst Secretary of Education we've seen," said Warren, a former public school teacher, in an email to supporters on Monday ahead of a speech Monday before the American Federation of Teachers in Philadelphia.
"She and her team are up to their eyeballs in conflicts of interest. Instead of championing our students, they protect for-profit colleges that break the law and cheat them," Warren said.
Warren has been an aggressive critic of DeVos since the former philanthropist was appointed by President Donald Trump, and she established herself as an education hawk early on when she grilled DeVos at her confirmation hearings.
Noting that the Department of Education manages a trillion dollar loan bank, Warren asked whether DeVos had ever run a loan program or taken out student loans herself.
The answer to both questions was no.
"So you have no personal experience with college financial aid or management of higher education," Warren concluded at the end of her line of questioning, which was shared widely in Democratic circles and used as a rallying cry to protest DeVos' confirmation.
Despite being one of the longest serving members of Trump's cabinet, DeVos has continued to be a focus of controversy throughout her tenure as the head of the Education Department. Just last week, she criticized reporters for using her name as "clickbait."
Since the fiery exchange with Warren at her confirmation hearing, DeVos has looked to curb the growing student debt crisis. Earlier this year, DeVos endorsed a proposal that would limit the amount available for certain federal loans. However, that proposal also received backlash from Democrats who said it could limit access to higher education for individuals who might not qualify for other types of loans.
Late last month, Warren established higher education reform as a key platform in her campaign, revealing an ambitious plan that would cancel student loan debt for millions of Americans and eliminate tuition for two- and four-year public colleges.