WHEN ANA BARROS first stepped into Harvard Yard as a freshman, she felt so out of place she might as well have had the words “low income” written on her forehead. A girl from Newark doesn’t belong in a place like Harvard, she thought, as she marveled at how green the elms were, how quaint the cobblestone streets. Back home, where her family lives in a modest house bought from Habitat for Humanity, there wasn’t always money for groceries, and the world seemed gray, sirens blaring at all hours. Her parents, who immigrated to the New York area from Colombia before she was born, spoke Spanish at home. It was at school that Barros learned English. A petite 5-foot-2 with high cheekbones and a head of model-worthy hair, Barros found out in an e-mail that she’d been accepted to Harvard — a full scholarship would give her the means to attend. “I knew at that moment that I’d never suffer in the way that my parents did,” she says.