The Government has been warned it needs to build more schools and classrooms to meet a bulge in class rolls.

An April Ministry of Education paper shows 139 schools were over capacity.

Migration last year brought almost 21,000 extra school children.

Ormiston Senior College principal Tim Botting says his school has had to adapt.

"We've had to use some of the café space, our library space now has students in it. We're coping really well, our staff have adapted, our students are doing well in the space."

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