"This is a window into the future. All of the academic research shows you that these open, modern learning environments, with bigger classrooms, but with shared teachers, they are the way of the future, the way of making sure we life the professional development of teaching, but also doing the very best for our kids."
The first stage of Pegasus Bay School consists of a library, administration, resourcing and hall, and teaching areas for 420 children.
The second stage will provide two teaching blocks for another 180 students, and that work will start once the current school reaches capacity.
Mr Key walked through the open classrooms, joined by an internal hallways, and was impressed by what he saw.
"It's a brilliant school," he said.
While not learning at desks, children were hard at work on cushions, small pods of chairs, or lying on the floor.
It replaces the old Waikuku School, which dated back to 1873.
It's a "far cry" from the latest building, Education Minister Hekia Parata says.
Ms Parata and Mr Key said that while Christchurch "went through a lot" while the government unveiled its education shake-up for the region, Pegasus Bay School has set the example for other schools as to what can be achieved.
"In the end, it's like all of those things -- people often resist change, but when they actually get to see the new product -- as we said at the time of the debate -- parents will be flocking to bring their [children] here," Mr Key said.
"I think this is a sign of the success of the programme."
- APNZ