Nearly half of NCEA students failed this year's online numeracy test

Results show only 55 percent passed in numeracy, 66 percent in writing - and 70 percent in reading.

Students must pass all three before they can receive any NCEA qualifications, when they complete secondary school.

Secondary Principals' Association President Vaughan Couillault says it's clear why they're failing.

He says there's a clear numeracy and literacy problem and many students arrive in year 9 well behind where they need to be.