A Jan. 23, 1985 Montreal Gazette article concerned with the closing of Malcolm Campbell High School can be accessed here.
A Dec. 18, 1986 Montreal Gazette article provides additional information.
If anybody knows details about the closing, which I assume was in 1987 – for example, was there a final assembly?; are photos available of the last day of school?; does anybody have a first-hand recollection of the day it closed? – please let me know.
The school building now serves the local community as L’École Arménienne Sourp Hagop.
A useful reference regarding the history of Protestant (or, to be more precise, a segment of non-Roman Catholic) education in Quebec is A Meeting of the People: School Boards and Protestant Communities in Quebec, 1801-1998 (2004).
A review of the study is available here.