Students at more than 400 schools across New South Wales have experienced glitches while sitting the online NAPLAN tests.

The Australian Curriculum, Assessment and Reporting Authority (ACARA) is investigating the issue.

NAPLAN online is being conducted at about 50 per cent of schools while it is expected to be rolled out to the rest next year.

State Education Minister Sarah Mitchell tells Chris Smith schools can revert back to pen and paper if necessary.

“I am not happy with what has happened with NAPLAN this week.

“Clearly the platform isn’t up to scratch.

“The idea, I think, theoretically is a good one… but to be frank, Chris, that only works when the internet and the platform works.”

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