Turnbull is affiliated with the three Catholic Primary Schools in its Catchment area, St. Matthew's[6] and St. Helen's[7] in Bishopbriggs and pupils from Torrance who attend St. Machan's[8] in Lennoxtown.

The original school campus was constructed in 1974 by the Lanarkshire Education Authority Architects' Department to a design by Robert Forsyth.

An extension to the main building was opened in September 2002 and provided pupil recreational areas, offices, a staffroom, S6 Common room and a larger School library.

This was undertaken as part of a £134 million East Dunbartonshire Council Public-Private Partnership project to build six new secondary schools.

[15] From April 2007, the former Auditorium, Music and PE block was demolished and the Maths annexe relocated, in order to facilitate the start of construction on the new building.

The main building consists of two wings of accommodation to the west and east, which are linked by a central atrium, housing an internal courtyard, the cafeteria, an auditorium and performance space.

The new building was completed for the start of the August 2009 term and was officially opened on 21 September 2009 by Councillor Una Walker, Education Convener of East Dunbartonshire Council.