New Zealand might be spending more on education than other countries, but our class sizes remain large.

A new report has found New Zealand spends 5.5 percent of our national income on schooling  - the seventh-highest in the OECD.

Parents and other private sources pay almost eight percent more than the OECD average.

New Zealand Initiative chief economist Eric Crampton told Mike Hosking large classes aren't a bad thing if you have good quality teachers.

But he's concerned teacher quality isn't as high as it should be.

Crampton says large classes aren't a bad thing if you have good quality teachers.

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