Right on schedule, just as schools gear up to begin the new year, the issue of educational achievement has come back into the headlines.

As revealed in this newspaper last Sunday, Auckland Grammar School will this year direct all its fifth-form (Year 11) students to do the University of Cambridge international exams rather than the NCEA programme.

Some exceptions will be allowed for "weaker" students in maths and English (the latter presumably include non-native speakers), but essentially the school will be spurning the state-sponsored secondary school assessment system in favour of a qualification benchmarked to the UK's GCSE standard and administered by a department of that fabled university expressly created for the purpose.

As if on cue, the chorus of disapproval began: the school's decision was elitist, critics charged - a description its board of trustees would probably not dispute - and undermined the national qualification (it was not explained how it accomplished this).

It is idle to attempt in a few hundred words to assess the competing merits of NCEA and the Cambridge exams. Those genuinely interested can easily enough access online dispassionate analyses from qualified people without a political axe to grind; those who have already made up their minds are unlikely to be convinced by brief argument, no matter how pithy.

What does deserve examination, though, is whether Auckland Grammar is entitled to spurn NCEA. In making it available on demand, it recognises that state funding is contingent on offering it, but in practice it will cease to exist at Year 11 - and parents are, by all accounts, warmly supportive of the move. Other schools may follow.

Some of the responses to Grammar's announced intention have been immoderate, if not silly. PPTA president Kate Gainsford called on Education Minister Anne Tolley to sack Grammar's insubordinate board of trustees if the school did not reverse its decision.

Others called Cambridge a "Third World" examination, a demonstrably false assertion presumably derived from the role Cambridge once played in administering examinations for the civil servant class in the colonies of the Empire.

It was left to Professor John Hattie to make the obvious observation: that Grammar was answering the demands of its constituency and engaging in another of the branding exercises that more than 20 years of educational reforms have made de rigueur in the sector.

It may well be, as Grammar headmaster John Morris claims, that an assessment method that leans heavily on end-of-year examinations suits his boys better than the continual grind of coursework assessment.

The school plausibly argues that pupils can more readily pursue sporting and cultural goals in term time if the regular deadlines for assignments are not always looming.

Most of the early criticisms of NCEA have evaporated now that the system is bedded in; it has plainly helped some of the poorest (and poorest-performing) schools in the country to lift student achievement; and it is a vast improvement on the pass-fail exams of the past which defined half of each cohort as failures.

But Grammar is unashamedly an elitist school and if it wants to set its own standards, it should be allowed to. So long as the school satisfies its legal obligations, there is no reason it should not satisfy its customers too.

An incidental and regrettable aspect of the furore has been the predictable invisibility and silence of Minister Anne Tolley. Characteristically, she initially issued an anodyne statement through a spokesman, reiterating her support for NCEA. It took her the entire week to front the press.

Having been stripped of responsibility for tertiary education and having alienated most primary schools over "national standards", she has surely earned the right to surrender her ministerial warrant. In an election year, such a poor performer in such a key portfolio is a liability John Key can do without.