In 2011, Joseph Mizzi found himself in Zambia, the landlocked nation in southern Africa. As a volunteer for World Bicycle Relief, he was part of a mission to provide schoolchildren with wheels to alleviate their sometimes hours-long commute on foot. But the builder in Mizzi—he is president of New York-based Sciame Construction—had other ideas. “I thought, rather than give them bikes to travel the long distances to school,” he recalls, “why not build more schools?”