The Ministry of Education and the New Zealand Qualifications Authority are being called on to release national school statistics at the same time as students get their marks back.
As thousands of students hunker down for National Certificate of Educational Achievement (NCEA) and scholarship exams, Secondary Schools Principals' Association president Patrick Walsh told the Herald that national averages comparing schools' results were released "very late" by NZQA.
Students traditionally get their results back in mid-January, while schools get their data back at the end of January and can look at other schools' results from mid-February.
The data is made public by March.
But Mr Walsh questioned why national data could not be released earlier - allowing schools to compare themselves with others in the same decile group, analyse differences and make timely reports back to their boards and communities.
"We've consistently asked that once the results are given to students, that the ministry and NZQA provide data early on national results," he said.
"It helps us in terms of planning - and to know what subjects we've done well in, in comparison with schools of a similar type."
NZQA deputy chief executive Richard Thornton said the delays were kept as a "courtesy - and also to be bit cautious".
"You might get results that will change - students may appeal results of exams and we will have to check all of these," he said.
"And even though kids get their results in mid-January, they won't be finalised until the end of January anyway, because of appeals and corrections."
Straight after the checking has been done, the schools will have access to their own information.
"We also give those schools time to check, otherwise we could put information out on a school that they could challenge or is wrong."
It also gave them time to go to their boards and communities first.
"If for some reason their results had dropped or risen, they can go out and tell their own story before the public starts descending on them with their "Why is it like this?" questions."
For NZQA, the exam period came after a year of preparation behind the scenes.
A staggering 1.4 million standard entries had been entered this year, with a high number of pupils sitting exams across all three levels.
"Organising the national NCEA examinations is a mammoth task - the number of students going into examination rooms this year could fill Eden Park three times over," Mr Thornton said.
Exam papers, subject to five cycles of checking, are completed a year in advance.
NZQA is now in the final stages of finishing the 2013 papers.
For the 143,000 students from around the country sitting NCEA exams for levels one, two and three for the next four weeks, the heat was on.
Year 11 students will have their first taste of exam pressure when they sit the English examination this morning. The session is the biggest out of all the exams across the levels, with more than 46,000 students sitting.
Other exams today are Year 12 German and Economics, Year 13 Samoan and Te Reo Maori and Scholarship Japanese and English.
"The stakes are high for kids because of the economy, the shortage of jobs and the cost of going to university - they don't want to get it wrong," Mr Thornton said.
Mr Walsh said while students should have begun preparing for exams back in February, many students - especially boys - took to "cramming" in the last weeks of the year. "Overall, that's not a very successful approach."
The NCEA system also created an issue where some students who had already achieved NCEA levels after gaining enough internally assessed credits took a relaxed approach to exams.
"It means some students don't bother turning up to exams or some don't complete them - and it's difficult to motivate them to do their best when they know they've already passed."
When: Today until Tuesday December 4.
Who: More than 143,000 students sitting exams this summer.
1,412,000 entries in NCEA and Scholarship exams.
120 exam sessions.
400 exam centres throughout the country.
4600 exam supervisors.
Biggest exam session: Level 1 English (46,000 students).
Smallest exam session: Scholarship Latin (19 students).
Level 1: 63,965 candidates.
Level 2: 56,011 candidates.
Level 3: 39,618 candidates.
NZ Scholarship: 10,335 candidates.
What's on today
Level 1 English.
Level 2 German, Economics.
Level 3 Samoan, Te Reo Maori.
Scholarship: Japanese, English.