Construction for the Thayer Academy Schoolhouse began in January of 1876. The Board of Trustees for the school held an architectural completion to choose the design. A firm by the name of Hartwell and Swazey won the competition and their design for the schoolhouse was chosen. The exterior of the school was completed by November and by August of 1877 the Academy was poised to open its doors for its first class.
Gas lighting, steam heating, up to date plumbing and ventilation systems were included in the construction and concrete was poured between the walls and between the floors to prevent the passage of sound and the spreading of fire. Thayer Academy’s first class was comprised of 26 students, one of which being the son of Asa French.