McClelland received his bachelors, masters and Ph.D. all from the University of Pennsylvania in 1903, 1912 and 1916 respectively.
He began his teaching career as an English instructor at City College of New York in 1903.
In 1924, he was made a full professor of English, a position he held until he was given emeritus status in 1950.
He then became vice president in charge of undergraduate schools, a position he held until his appointment as provost in 1939.
[2] After he stepped down as president in 1948, McClelland served as a trustee of Penn until his death in 1955.