Academic interests and career
Among other topics, Shenton lectured on 19th-century American history, World War II, and the history of immigration and ethnicity in the United States. He also habitually taught Contemporary Civilization. Beyond Columbia, he taught at Montclair College, the Manhattan School of Music, and the Katherine Gibbs secretarial school, as well as holding televised classes on New York's PBS station.
Positions on campus issues
Shenton was known (probably among those who held the same views on issues) as a "conscience of the Columbia faculty". He supported the 1968 protests and served as the go-between for black and white protesting students. He was among other professors who formed a human chain to physically block violence from breaking out during the protests' building occupations. When the police broke up the protest, he was among those severely injured.
Later, he encouraged students seeking divestment from South Africa.
Shenton "won every award possible for a Columbia teacher", including the Mark Van Doren Award given out by students (1971), the Great Teacher Award of the Society of Columbia Graduates (1976), and the Presidential Award for Outstanding Teaching (1996).
Although he was known as a tough grader ("he continued to give C pluses and B minuses long after these grades had disappeared from the repertoire of other teachers"), his teaching inspired alumni such as Eric Foner, Sean Wilentz, and Thomas Sugrue to go on to become historians themselves. This possibly had to do with his personal touch: remembering students from lecture classes twenty years later, and grading all papers and exams himself.