Kindergartens and child-care centres may be roped in to help track vulnerable children when a new integrated enrolment system starts in 2014.
Children's Commissioner Dr Russell Wills says preschool education providers should be required to chase up families and find out what is going on when a child stops attending.
But the Early Childhood Council says private child-care centres are not set up for social work, and chasing families should be left to the Government.
Dr Wills, a Hawkes Bay paediatrician, has been involved in health-sector initiatives to track children who do not turn up for immunisations and before-school health checks. Social workers made sure 85% of even the poorest children in the region got their before-school checks last year. He said a similar system was needed to make sure the poorest children had access to early childhood education.
Almost 95% of all year 1 primary school pupils in the year to last June had attended some kind of preschool education. But the proportion ranged from 99% for schools in the richest tenth of the country to 81.8% in the poorest tenth.
Ethnically, previous preschool attendance ranged from 98.2% for European children and 96.3% for Asians, down to 90% for Maori and 85.9% for Pacific children.
The Education Ministry plans to call tenders later this year for an $18 million information system that will give all preschool pupils identification numbers and track their attendance in all kinds of education and child care.
