Check this page on the ERO website.

ERO reviews of the education of students exempt from attending a regular school

In the past the Education Review Office has reviewed the education of homeschooled students according to a schedule set annually. From 1 July 2009 ERO will carry out reviews only when requested by the Secretary for Education, or in other particular circumstances.

For further information about this change, please contact Rob Williamson, Senior Review Officer Homeschooling, or phone 0-4-499 2489.

Commentary on this can be found here.