Belmont-based Pindan has been awarded a $6.4 million state government contract to complete upgrades at Collie Senior High School.
Under the contract, Pindan will build a new classroom block and cafe, upgrade a number of buildings, and complete other minor works.
Work is expected to begin soon on the project.
Pindan won a $7.8 million contract in August to design and build a new bus depot in Mount Claremont.
In 2015, the company completed a $45 million upgrade at Kalgoorlie Boulder Community High School.
The project comprised the construction of new teaching blocks, a cafe, playing courts, visual arts, and education support hub.