“The time for half-measures is over,” the Democratic presidential candidate said. : On Monday, Sen. Elizabeth Warren (D-Mass.) released a wide-ranging plan to fix the U.S. college system, with proposals including making two-year and four-year public college free and expanding the size and scope of the federal Pell Grant program. And one particularly radical idea is sure to grab the attention of young people around the country: wiping out student loan debt for the vast majority of American borrowers.