The latest foundational assessment data shows 95 percent of socio-economically disadvantaged children were below curriculum level for maths in Year three.
70 percent of them were more than a year behind.
Hora Hora school principal Pat Newman told Heather du Plessis-Allan that children in lower-income families face more uncertainty and disruption.
He says people who don't know whether food's on the table or if they're sleeping in a car will be behind.
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