Children are falling behind other students in their schoolwork, as the housing crisis forces record numbers of families to change schools.

New figures show 36,000 students shift schools once a year. Of that number, 3400 move twice.

Sylvia Park School principal Barbara Ala'alatoa told Mike Hosking 20 percent of her students are always moving schools.

She said the housing market is usually the main contributor because families move out of the area to try find cheaper rentals.

Ala'alatoa said changing schools is a massive deal for students, and will absolutely affect their learning.

"When you're new, and if you're changing, that confidence doesn't grow over time, so those are the things that we have to make sure we mitigate at school."

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