“Dud teachers” have been blamed for Australia’ decline in academic results in a “brutal” speech to private independent schools on Thursday.

Acting federal education minister Stuart Robert said the bottom 10 per cent of the nation’s teachers were not up to scratch, and angered public school leaders by praising private schools for employing only quality teachers and delivering model examples of education.

He told Liam Bartlett on 6PR Mornings a dense curriculum was also to blame for a plummeting performance in international education benchmark tests, despite increased funding of the sector.

“We have been consistently slipping at the same time the Commonwealth government has doubled the amount of money into education,” Mr Robert said.

“We have to ask ourselves what the issue is, and we believe it comes down to curriculum… and how we’re educating our teachers and that classroom environment.”

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