The board has engaged the services of an external consultant to work with trustees and school leaders.
"The school has some very high achievers, which is great, but there is a gap for lower performing students and we want to see all students achieve," Mr Southee said.
"The role of the consultant has been to help us draft a plan of action to lift the achievement of all students."
The ERO report cited changes of leadership as affecting the continuity of the Maori department, but said school personnel were working to develop partnerships with Maori students, teachers, parents, whanau and local iwi.
ERO assessors found "good quality inquiry processes emerging from some faculties and individual teachers are focusing on effectiveness for student learning and engagement".
"Findings are leading to practices likely to be positive for Maori and all learners."
The school's performance in NCEA has been above the national rates for similar schools.
However, the report said that a "well-co-ordinated internal evaluation would generate better information to target improvement opportunities, including success for some disengaged students".
When the on-site part of the review was conducted last August, the school roll was 1494 with 53 per cent male and 47 per cent female students.
There were 27 per cent Maori students, with the school hosting 71 international students from seven countries.
The Education Review Office intends to carry out another review within the next two-and-a-half years.
