Theodore Ryland Sizer (June 23, 1932 – October 21, 2009) was a leader of educational reform in the United States, the founder (and eventually President Emeritus) of the Essential school movement and was known for challenging longstanding practices and assumptions about the functioning of American secondary schools. Beginning in the late 1970s, he had worked with hundreds of high schools, studying the development and design of the American educational system, leading to his major work Horace's Compromise in 1984. In the same year, he founded the Coalition of Essential Schools based on the principles espoused in Horace's Compromise. Life and career Sizer was born in New Haven, Connecticut, the son of Caroline Wheelright (Foster) and Theodore Sizer, Sr. (1892–1967), an art history professor at Yale University. He received his B.A. in English from Yale in 1953 and subsequently served in the Army as an artillery officer. He later described his experience leading soldiers in a democratic and egalitarian fashion as a formative influence on his ideas about education. After teaching in high schools, he earned his masters and doctorate in education from Harvard University in 1957 and 1961, respectively. He was a faculty member and later dean of the Harvard Graduate School of Education, a position he held during the 1969 Harvard student strike. While dean, he reorganized the school into seven departments, expanding the resources available for research (particularly in the area of urban education), while expanding minority enrollment. In 1970, he received a Guggenheim Fellowship for Education. Sizer left Harvard to serve as headmaster of Phillips Academy in Andover, Massachusetts from 1972 to 1981, to lead a study of American high schools sponsored by the National Association of Secondary School Principals and the National Association of Independent Schools. From 1983 to 1997, he worked at Brown University as a professor and chair of the education department, and in 1993, he became the Founding Director of the Annenberg Institute for School Reform. During his years at Brown, he produced most of his books, including Horace's Compromise. In it, he examined the fundamental compromise at the heart of allegedly successful American high schools. He suggested that the students agree to generally behave in exchange for the schools agreeing not to push them too hard or challenge them too severely. Thus, he widened the scope of schools that were failing to do their best to educate children far beyond the traditionally