Located in the southern part of town, the site in 1922 was covered in thick bush and drainage of the ground proved an early problem.

In the first year, Greymouth High School offered classes for Third, Fourth and Fifth Forms, commercial (two) and engineering.

A school cadet corps flourished in 1923 and a camera and dramatic club were established in 1924.

A homecraft block was added in 1940 comprising dressmaking and cooking rooms, laundry and model flat and completing a four-sided arrangement of buildings.

From 1953, a period of great expansion commenced when a technical drawing room and two extra classrooms were built.

In 1957 this was expanded by the addition of a dormitory and ablution block and the enlargement of the dining room and kitchen facilities.

[6] Greymouth High School established Māwhera Services Academy (MSA) in 2002, a military oriented course, with funding from the Tertiary Education Commission, New Zealand.