The smallest of three wooden schoolhouses that Edmund March Wheelwright designed during his term as Boston city architect (1891–1894), Oak Square School represents the end of a nineteenth-century architectural tradition. In his influential book School Architecture (1901), Wheelwright presented the Oak Square School as an example of the Old Colonial model for modern educational needs. Fronted by a Tuscan portico and ennobled by a copper-covered cupola, his original two-room building was enlarged in 1923 by the addition of a block to the rear, forming a T-shaped plan.
The building was the third public school in Oak Square, the previous two having stood in the center of the square under majestic oak trees. Overlooking the square are two other fine municipal buildings. The Faneuil Branch of the Boston Public Library (1931, 419 Faneuil Street) is an Art Deco design by Kilham, Hopkins and Greeley. Next door stands Engine Company No. 51, a three-story two-bay brick structure by Maginnis and Walsh, better known for their Catholic church designs, such as the nearby Our Lady of the Presentation Church (1913–1921, 680 Washington Street), the latter being one of the firm's finest exercises in an Arts and Crafts Gothic mode.