David has taught elementary, middle school and high school students in public and private schools, as well as community college and teacher preparation courses, in New York City and Vermont. David still spends as much time as possible in schools with teachers and children. Together with Meredith Liben, David founded two innovative model schools in New York City - New York Prep, a junior high school in East Harlem, and in 1991, the Family Academy - where he served as Principal and lead curriculum designer. David synthesized the research behind the Common Core State Standards in ELA, and, with his wife Meredith, was part of the research team that determined the complexity levels for the standards. David holds a bachelor's degree in Psychology from the University of Wisconsin and a master's degree in school administration from Teachers College, Columbia University.