LAST YEAR, FEDERAL education officials did something they almost never do: They wrote off more than $3 million in student loan debt belonging to nearly 500 students. Short of dying or paying them off, students almost never shed their college debt, even through bankruptcy.

When it abruptly closed its doors for good last January, the American Career Institute, a for-profit college with five campuses in Massachusetts, left students stranded in dire financial straits: They won’t get the job training or certificates they paid for, but they remain on the hook for student loans they can’t afford.