Significant upgrades are planned at Sacred Heart Catholic School in Port Lambton.
The provincial government is investing $3.1-million to replace a 34-year-old portable with two new classrooms and two new washrooms.
They'll also add 46 new elementary student spaces, 49 licensed childcare spaces, and three new child care rooms.
St. Clair Catholic District School Board Associate Director Amy Janssens said the spaces will fill a growing need in the community.
"That's something that we checked in with the County of Lambton on, and they told us that there was a need and so we responded and included them in the application," she said. "We're quite eager to start construction. We have hopes of starting in July of 2021 and, pending the start date for the construction, we see completion by September of 2022.
Janssens said the province is funding the entire cost of the project.
The funding is part of the Ontario government's $500-million investment to build 30 new schools and make upgrades to 15 existing facilities.
Ontario is also providing school boards with $1.4-billion to renew and maintain existing schools.
The government said that money could be used to replace aging heating or air conditioning systems, repair roofs and windows, and install important accessibility features like elevators and ramps.