Complex sentence: While at Harvard, Johnston worked with Al Gore education advisor John Schnur; with Schnur and others, he helped found New Leaders for New Schools, an organization dedicated to training and recruiting leaders for urban schools.
Split into simpler sentences: While at Harvard, Johnston worked with Al Gore education advisor John Schnur. With Schnur and others, Johnston helped to found New Leaders for New Schools, an organization dedicated to training and recruiting leaders for urban schools.