The Secondary School Principals' Association fears Maori and Pacific students will be marginalised if a proposal to make university entrance tougher goes ahead.
The Qualifications Authority would like to see level three of the NCEA made a prerequisite for university study - doubling the number of credits currently needed.
To pass level three a student needs 60 level three credits and 20 other credits from levels two or three; university entrance currently requires only 42 level three credits.
The authority's chief executive, Karen Poutasi, says that only 5% of school-leavers who go to university do not have level three, and that under the changes most students would still get in.
Secondary School Principals' Association president Patrick Walsh says schools have just started getting traction, with more Maori and Pacific students gaining entry to university, and making the standards higher may reverse that.
Student body questions change
Students' associations are questioning the relevance of the proposed change.
Union of Students' Associations co-president David Do says universities are already setting their own prerequisites individually, and he says in some cases that level is above the current university entrance standard.