into disrepair in the late 18th century, pupils were taught in the vestry of St Denys' Church until the school was closed in 1816. In 1826, the trustees purchased a house on Northgate at the cost of £545 3s. from one Mr Squires. In 1834, the Chancery Court agreed to fund the rebuilding of the school according to plans by the Sleaford architect and builder Charles Kirk, who constructed it at a cost £1,168 15s. The building is in the Tudor Gothic style and built in Ashlar stone with slate roofs. It has three stories of three bays, with the upper floor housed in two gables. A shield with the arms of the Marquis of Bristol and his wife are located above the four-centre arch doorway. Single-storey wings exist on either side in a similar style. Brick additions were made in 1904 and 1906. As the school roll grew, the old buildings became too small. A major building programme began in the 1950s: £128,000 was set aside to rehouse the school in purpose-built facilities adjacent to the existing school-houses. The first phase was opened in 1956 and included art and handicraft rooms; the second phase was completed in 1958 when physics and chemistry rooms were added; and the third came in 1965 with the opening of new biology and general science laboratories alongside other classrooms, while the following year saw a new hall/canteen and kitchen open. The final phase consisted of eight further rooms, built shortly afterwards. A grant of £650,000 funded the construction of a technology centre with a computer suite, which opened in January 1993. Plans for a new sports hall were first discussed in 1990, but they only came to fruition in 1996, when Northgate Sports Hall opened. The Sports Council and the Foundation for Sport and the Arts donated £250,000 towards its construction; this was matched by North Kesteven District Council, while Carre's raised £50,000 towards the building work. An all-weather pitch at the school opened in 2007; it cost £649,000 to lay, half of which was met by the Football Foundation. A building programme costing £835,000 provided the school with food technology facilities and a two-storey Fitness Suite, which were opened in March 2011. As of 2022, the food technology facilities are unused and the room now supports the Sleaford Joint Sixth Form in study work. Headmasters The indenture of 1604 made it compulsory that