As you said you making statistics report on Washington DC education system, so for your help here I am providing list of colleges/universities located there:

American University

Catholic University of America

Gallaudet University

George Washington University

Georgetown University

Howard University

Institute of World Politics

National Intelligence University

Pontifical Faculty of the Immaculate Conception at the Dominican House of
Studies

Pontifical John Paul II Institute for Studies on Marriage and Family at The

Catholic University of America

Strayer University–District of Columbia

Trinity Washington University

University of Phoenix–Washington DC Campus

University of the District of Columbia

University of the District of Columbia David A. Clark School of Law

University of the Potomac–Washington DC Campus

Washington Theological Union

Wesley Theological Seminary