Arne Duncan used to boast about the rising high school graduation rate, but he never talked about one cause of the increase: online credit recovery.

Slate has run a multi-part series on the online credit recovery racket. Imagine a student failing a one-year course, then earning full credit in less than one week. It has its benefits: superintendents get praised for the steady increase in the graduation rate; students get the credits they need to graduate.

But what they don’t get is an education.

This segment begins:

“After she failed English her junior year at Riverbend High School in Spotsylvania, Virginia, 17-year-old Amelia Kreck had to retake the class. It took her two days.

“In the classroom, Amelia had struggled with essay writing. But the online course her school directed her to take as a replacement had no essays. Nor did Amelia have to read any books in their entirety. Unsurprisingly, she says, she never had to think very hard. That’s because she skipped out of most units through a series of “pretests” at the start, which she says contained basic grammar questions as well as some short readings followed by multiple-choice sections.

“Amelia says she enjoyed some of the readings in the online version of the class, created by for-profit education company Edgenuity, including excerpts from Freakonomics and the writings of the theoretical physicist Michio Kaku. She also appreciated the flexibility to work from home—until after midnight on one of the two days it took here to recover her credit. But “there was a big component of the original class that was missing from credit recovery,” she says. “Most of it was on the shallow side.” She finished so quickly, she says, that “I didn’t improve in the areas that needed improvement.”