In the early 1930s the need for a second NDG high school was recognized. However first the Depression and then World War II served as major roadblocks in considering a second NDG high school to reduce overcrowding at West Hill High. The school had outgrown its earlier additions and by 1944 had peaked at a population of 1452 students and 50 teachers.  By that year a new school design was approved by the PBSC and it was to be known as Somerled High School, located on the corner of Somerled and Draper avenues. A further delay occurred when the PBSC was absorbed into the newly created Protestant School Board of Greater Montreal in 1946. A subsequent evaluation of school properties and requirements confirmed that any further extension of West Hill High was not the best solution, and that work should begin on the new school, now to be called Monklands High School. Work on this new school finally began on June 2, 1950.

By 1952 with the long-awaited second NDG high school nearing completion a new assignment was planned  for the original school. Unexpectedly, the new role also involved a name change. In September the new school, originally to be called  Monklands High School, opened instead as West Hill High due to lobbying from the students. The old school had lost its original name and was hurriedly renamed Westward School and became a junior high, which accommodated grade  7 & 8 students. By 1954, however, the impact of the ongoing "baby boom"  was realized and the PSBGM was forced to reinstate the school as a full high school and began adding senior years to its curriculum one year at a time. In 1955 a new name was assigned, Monklands High School, the name originally intended for the the new high school built on Somerled Ave. Along with its restored academic role the school received a whole new annex on Benny Avenue and a new gymnasium for girls in 1958. See the Name Game for details

Enrolment at Monklands High peaked in 1967  but at a level much lower than the mid-1940s numbers and declined steadily into the mid-1970s as the "baby boom" tapered off.. By the late 1970s large scale changes in the local population, accelerated by government language legislation led to final, dramatic enrolment declines  which led to the closing of the school in  June 1979.See the rise and fall of enrollment numbers See the Gazette article on the closing of the school
 

Unlike other older schools, the building was not demolished but instead  lay unused for four years while the PSBGM and the city argued over its fate. In 1984 work began to transform the building into a seniors residence. In addition to the existing building, the soccer field to the Terrebonne side became site of two new buildings added as part of a residence complex.

List of Monklands High Staff 1957-1979