A Western Bay school has bucked a national trend with only one in 10 NCEA internal assessments marked incorrectly after moderation.
NCEA internal assessments are set and marked by teachers, with grades checked by other teachers and samples in turn checked by NZQA.
A moderator reviewed a student's work and considered if the teacher had correctly judged whether the work had achieved or not achieved the standard.
Last year, the nation-wide agreement at the level of grade was 76 per cent - meaning moderators disagreed with almost one in four grades awarded.
Te Puke High School deputy principal David Crone said assessments were moderated at the school as well as through NZQA which contributed to a more than 90 per cent agreement rate between the school and the moderators.
"We find a much lower number of differences in the moderator's opinion and that of the teacher. This can sometimes mean either a higher grade or lower, it is not always a lower result.
There is always the potential for different interpretations around the mark schedule and not necessarily a major shift."
Mr Crone said the moderation system was robust and provided good feedback to the teachers about their marking. "It is intended to allow staff to see how they are marking to the national standard and where there are areas of concern, they can make alterations based on the comments received from the moderators." There was no absolute answer under a standards system which meant there was always room for variables in marking, Mr Crone said.
Aquinas College principal Ray Scott said for internally assessed standards there was internal moderation within the school. This included shared marking within faculties and staff doing check marking of assessments for each other.
Mr Scott said there was also co-operation between local schools for moderation and check marking.
He said there would always be some variance between markers, but in the school's experience there was a good level of agreement between the school and moderators.
Mount Maunganui College principal Russell Gordon said he was surprised a quarter of assessments were deemed incorrectly marked.
He said schools had regular external reviews of their assessment process completed by NZQA and this would highlight any issues schools may need to address to improve agreement rates.
"I am confident with the agreement rate around our internal assessments at Mount Maunganui College. This confidence is supported by our external review of our internal procedures and by our own rigorous internal reviews."
NZQA deputy chief executive Richard Thornton said there was always the potential for some disagreement, for example, in the assessment of an art portfolio where interpretation can influence the final judgment. Additional reporting by New Zealand Herald