In 1961 he became the Frederick A. P. Barnard Professor of Education and a member of Columbia's history department, directing the Teachers College's Institute of Philosophy and Politics of Education in 1965-1974 before becoming the college's 7th president in 1974–1984, after which he returned to teaching and research.
At the Teachers College, Cremin broadened the study of American educational history beyond the school-centered analysis dominant in the 1940s with a more comprehensive approach that examined other agencies and institutions that educated children, integrating the study of education with other historical subfields, and comparing education across international boundaries.
The historiography of education turned bitter in the 1960s, as New Left radical historians denounced the history of American education as a failure when it came to promoting democracy and equality. Cremin avoided the debates, although in 1977 he did make clear his support for the traditional liberal interpretation. While admitting that occasionally educational institutions, being human, “have been guilty of their full share of evil, venality, and failure" he argued:
Contrary to the drift of a good deal of scholarly opinion during the past ten years, I happen to believe that on balance the American education system has contributed significantly to the advancement of liberty, equality, and fraternity, in that complementarity and tension that mark the relations among them in a free society....The aspirations of American education have been more noble than base, and that its performance over the past two centuries has been more liberating of a greater diversity of human energies and potentialities than has been the case in most other eras and in most other places.