School children should spend no more than half their day on computers

A group of parents has concerns some kids are spending up to 90 per cent of their day on screens.

'Sensible Screen use in Schools' wants to see evidence-based guidelines around screen use - with time on digital devices increasing as children get older.

Auckland physiotherapist Julie Cullen founded the group and says there's huge variation in screen use in school.

She says some only use devices moderately, but others - including primary schools - use them nearly all the time.