Principals Federation leaders say the country's reputation for having one of the best schooling systems in the world will be compromised, if schools don't work collaboratively together.
Government ministers have indicated they will may release league tables for primary schools, so parents can judge how well schools are doing.
Prime Minister John Key says that league tables for primary schools are a good way for parents to get information on how schools are performing.
But the federation's vice-president, Phil Harding, says that will lead to competition.
He says schools need to work together with the Ministry of Education to maintain high standards.
The ministry says it supports collaboration between schools, and says it is working on ways to best present school information, taken from National Standards data, that is accurate and cannot be misinterpreted.
Separately, an education expert says New Zealand schools risk losing their high ranking in the world because of complacency and a lack of collaboration.
John Hattie, former advisor to the Minister of Education on national standards, is now director of the Melbourne Education Research Institute at the University of Melbourne.
Professor Hattie says the Government's handling of the student-teacher ratio debate was a missed opportunity because it did not make it clear how changes would improve teacher quality.
Teachers and parents opposed the Government's plan to increase the student to teacher ratio for some school years, and it dumped the policy in June, some two weeks after it was announced.
Mr Hattie says instead of cutting class sizes, the money should be spent on paying teachers more. "Teacher pay is a major issue because it is so flat, and I think it's a major problem in terms of keeping the teachers in the profession."
Professor Hattie says New Zealand schools are still ranked in the world's top 12 but warns other countries are creeping ahead because they collaborate more.
"I think it's time we had a good look at what the metaphor is that we want to base our schooling on so we can maintain our excellence, but complacency is going to be our killer."
He says the decile system should be scrapped because it is wrongly used to measure quality, and he believes ERO reports give the best overview of schools' performances.
New Zealand Educational Institute president Ian Leckie last month told Morning Report that it would be "totally destructive" to education to make league tables out of national standards.
"To rank schools on a narrow measure really means schools will narrow their curriculum to the measures that are seen to be successful and that's not a step forward for New Zealand education.
"That's why the political view is just so far out of kilter with what's good for children."