“She’s like my older sister”— that’s not how most undergraduates think about their advisers. But it was the first thing that came to Elodie Oriental’s mind when she described Hanna Tenadu. “I go to her to explain everything I’m going through,” said Ms. Oriental, a daughter of Haitian immigrants who, with her twin sister, Ismaelle, shares the distinction of being the first in their family to go to college. “She’s the ear that listens to me cry.”

Ms. Oriental, an undergraduate at the City University of New York’s John Jay College of Criminal Justice and a budding criminal defense lawyer, is enrolled in a program known as ACE (Accelerate, Complete, Engage), CUNY’s response to the nation’s dropout problem. It’s an outsized success and the biggest reason is as old-school as fostering one-on-one relationships like Ms. Oriental’s.

Here’s a hair-on-fire statistic: In 2017, just a third of undergraduates at the nation’s public universities graduated in four years — the amount of time a bachelor’s degree is supposed to take — and even with two additional years, only 58 percent earned a diploma. The community college figures are even more dispiriting: 22 percent of students at public two-year colleges received an associate degree within three years and 28 percent within four years.

Dropouts may actually wind up worse off than if they hadn’t started college. While they earn a little more, they are likely to leave school with a pile of debt, but without the chance to pay it off by securing the high-paying jobs that a degree is supposed to open up. They are three times more likely than college graduates to be unemployed and four times more likely to default on their student loans, a statistic that wrecks their credit.