Theodore Sizer may refer to:
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Ted Sizer
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 practi ...
(1932–2009), leader of educational reform in the United States
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Theodore Sizer (art historian)
Theodore Sizer (March 19, 1892 – June 21, 1967) was an American professor of the history of art at Yale University and a director of the Yale University Art Gallery in New Haven, Connecticut. He was named the first Pursuivant of Arms for Yale ...
(1892–1967), American professor of the history of art
{{hndis, Sizer, Theodore