Hundreds of independent schools are considering adopting a new curriculum designed to encourage creativity and prevent teaching to the test.
The "independent curriculum" echoes the current secondary national curriculum - criticised by the Government as a "backward step" - because it includes skills such as independent thinking alongside subject knowledge.
Education secretary Michael Gove said there should be no place in the national curriculum for such skills and has commissioned a review that he wants to emphasise "essential" subject content.
Last month Mr Gove hailed Britain's private schools as "the best in the world".
But more than 250 of them are interested in taking the approach he has rejected, through the independent curriculum. At least 35 schools have already signed up within a week of its release.
Andrew Hammond, lead author of the new curriculum, said: "It is barely even written and already it is taking off. It is astonishing. Creativity and academic rigour are not mutually exclusive.
"Maybe the Government is missing that point."
The independent curriculum is aimed at fee-paying prep schools, many of which currently use the syllabus for the "common entrance" exam - taken as part of the admissions process to academically selective schools - as a basis for teaching in Years 7 and 8.
"The syllabus is a list of knowledge that you need to pass an exam, not a curriculum that makes for a full education," said Mr Hammond, a former prep school deputy head who used to help set the common entrance exam.
"A curriculum has to be much more than teaching to the test. It is about teaching skills such as discovery and communication," he added.
The new curriculum includes non-common entrance subjects such as music, drama and ICT, and aims to develop qualities in pupils including global awareness, tolerance, empathy and curiosity.
Mr Hammond had been "disappointed" by the narrow academic focus of the English Baccalaureate.
"It is about that core academic knowledge that children must have," said Mr Hammond.
"But where is the dance? Where is the music? Where is the drama?"
Many prep schools use the national curriculum as the basis for key stage 2 lessons, and Mr Hammond said the independent curriculum could be used to supplement rather than replace the state's version. It includes studies for Year 9 that could be used as extension activities for bright Year 8 pupils or adopted by senior public schools for their youngest pupils.
David Hanson, chief executive of the Independent Association of Prep Schools, said: "I welcome the independent curriculum because it shows there is still educational innovation in this country. Common entrance is still an aspect of the all-round education that prep schools provide and we will look to the independent curriculum to add to it where appropriate."
'It teaches pupils qualities for life'
Chris Jones, head of Copthorne Preparatory School in West Sussex, said he has adopted the independent curriculum because it is not "just about teaching children to pass an examination".
"It is about pupils becoming independent and creative so that they can apply, investigate and talk about their learning," he said. One of his staff members helped author the new curriculum.
"Common entrance is becoming less important because senior schools don't use it as much, but it has still been the basis for our curriculum.
"But if you say to yourself: 'We don't have to teach to that test' and you can adopt a curriculum that is more adventurous, and then along comes the independent curriculum, then that is brilliant, especially as it allows our pupils to continue to pass common entrance. It teaches pupils hugely important qualities for life."