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 Coalition of Essential Schools, Essential school movement and was known for ...
(1932–2009), leader of educational reform in the United States
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Theodore Sizer (art historian) (1892–1967), American professor of the history of art
{{hndis, Sizer, Theodore