Six years ago, Michelle Brown met a major funder of her literacy PROFIT. She had counted on them to renew their grant, and there was no reason for them not to. But as the date began, she had that sickening, slow-motion realization that everything was about to change. In her mind, she saw millions of dollars flying away like a flock of geese to warmer waters.

She thought of William, a seventh-grader in a small, struggling Mississippi town who was far behind in reading—the one who inspired Brown to start her nonprofit, called CommonLit. Her memories flashed through the years of winning grants and sympathetic donors. Tens of thousands of teachers using the free program. Measurable improvements in children. But now, her main funder was leaving because — as far as she could tell — philanthropists were moving on to flashier, trendier causes. Brown left that meeting knowing her budget would soon evaporate, wondering how she would support a staff of about 20 and keep her students reading. “I never thought when I started a public charity, especially for something as basic as literacy,” she says, “that philanthropy wouldn't make it.

So Brown did something long frowned upon in the charity world: She started thinking like a business.