The Old College, Outbuilding Adjoining Left Gable End Of College, Wall Adjoining Right Front Of College

The Old College, along with its adjoining outbuilding and wall, is a house that was originally built in 1508 as a grammar school, commissioned by Dame Thomasine Percival who funded its establishment. The building has undergone alterations and repairs in the 20th century. It is constructed of coursed polyphant stone with granite dressings and a slate roof. The structure represents a surviving portion of a larger complex, which includes New College and Hayescroft.

The building has a single-depth plan, with a left gable end chimney likely rebuilt, and a large rear granite stack featuring offset weatherings and a moulded granite cap, possibly with worn merlons. Granite coping and quoins are present on the right gable end. A rear left stair turret exists. The building is two stories high, with a four-window front. A central, moulded, granite four-centre arched doorway is present, featuring a shield in the tympanum and floral motifs in the spandrels. Ground floor windows have been renewed or repaired, with three-light casements featuring six panes per light and glazing bars, and new timber lintels. Two rear, three-light ground floor windows have pointed heads and hollow-chamfered granite mullions below square-headed hood moulds with label stops and diamond leads. A right-hand ground floor room serves as a hall, with a slate floor and a moulded granite fireplace, the lintel of which has likely been renewed. The kitchen to the left of the entrance features a renewed polyphant fireplace, a moulded granite arch into the stair turret. The staircase has been altered, with a moulded granite arch with an ogival apex leading from the stairs into the first floor, raised approximately 45cm. Principal roof timbers are visible in an upstairs room. Roof timbers were partly renewed, while remaining older timbers date back to the 18th century.

An outbuilding adjoining the left gable end of the college has two blocked rear windows with moulded granite jambs, one featuring a hood mould and label stops. A battlemented polyphant wall runs along the front of the building and along the street, with granite moulded coping to the merlons and embrasures. A narrow opening leads to a partially-blocked turret within the thickness of the wall on the college side, possibly for a bell ringing.

Dame Thomasine Bonaventure, born in Week St Mary, married Sir John Percival, Mayor of London in 1498. The foundation of Week St Mary Grammar School was modeled after the Macclesfield Grammar School founded in 1503 by Sir John Percival, and represents the third grammar school founded by a woman. An endowment deed for the school has survived. The building underwent alterations and repairs in 1975 by Paul Pearn for the Landmark Trust. An etching by Miss Hawksworth, based on a drawing by S Porut of the entrance, appeared in Relics of Antiquity or Remains of Ancient Structures, with Other Vestiges of Early Times in Great Britain, London (1811).