It was founded in 1919 by Dr. Clifford Pease Clark, and its headmaster was Dr. Frank Millett Morgan, both of whom were former members of the faculty of nearby Dartmouth College.
The school's primary purpose was "to prepare a boy adequately and thoroughly for College or Business, and to inculcate in him those basic principles and high ideals which tend toward the development of a manly character.
Prominent alumni included Dr. Morgan's son, Professor Millett G. Morgan (1915–2002), who was founder of the Radiophysics Laboratory at the Thayer School of Engineering and a leading researcher in ionospheric physics,[2] and the prominent hiking writer Daniel Doan.
[4] Several of the Clark School's buildings as well as its playing fields in Hanover were purchased by Dartmouth College.
[8] Significantly, the land acquired from the Clark School in central Hanover allowed Dartmouth to begin construction in 1956 of the Choate cluster, the first Modernist buildings on the college's campus.