Prime Minister John Key and Minister of Education Anne Tolley yesterday justified a $200,000 taxpayer-funded public relations campaign to sell national standards by accusing the teachers' union of protecting poorly performing teachers.

"There will always be those that resist change, who fear increased accountability and who put their own vested interests ahead of New Zealand's young people," Mr Key said.

"We will not bow down to those critics."

He said that inevitably national standards would identify some teachers who needed to change their ways and step up.

The New Zealand Educational Institute (NZEI) was "a union protecting their members".

Parents should not "have to put up with declining education standards, being kept in the dark about their children's progress or creeping political correctness in our schools."

Mr Key said many principals were not adequately sharing their school's achievement information with their communities.

"That is not good enough. National standards will demand schools and teachers do better in all of these areas and I make no apologies for that."

Details of an independent experts' group will be announced next week, but it is expected to include Professor John Hattie of Auckland University.

The NZEI has begun its own campaign against national standards and is calling for a trial.

The policy has been part of National's manifesto for the past two elections. It sets benchmarks of achievement for primary and intermediate students and requires schools to tell parents clearly whether their child has met the standard, or exceeded it or or fallen below it.

Mrs Tolley yesterday cited some damning statistics from the Education Review Office: 30 per cent of teachers were not teaching reading well.

She said 67 per cent of principals and senior staff were not tracking the achievements of pupils in Years 1 and 2 in reading and writing. That meant they could not give good information to parents, or could not be identifying children struggling in the early years.

A publicity leaflet, which has the National Party logo on every page, will be financed out of Mr Key's leader's budget and is very similar to the sort of election advertising National criticised Labour for producing under the Electoral Finance Act.

Deliveries to 350,000 households start today. Mr Key said MPs would be holding public meetings up and down the country to explain the policy.

NZEI president and school principal Frances Nelson said the campaign was the Government hitting "the panic button" as it realised opposition to the policy was growing.

Labour leader Phil Goff said the national standards had turned into a shambles.