Private schools have added to the chorus of criticism against the new curriculum for under-fives, due to be introduced later this year.
Independent schools do not have to follow the national curriculum once children reach school age. But the Early Years Foundation Stage curriculum sets out what provision parents can expect for their pre-school children in all settings, including the private, independent and voluntary sector.
By age four, about 39 per cent of children are receiving early education with private or voluntary providers, which includes day nurseries and childminders, four per cent are in independent schools, and 58 per cent in state schools.
The curriculum is due to become statutory in September, replacing the current guidance for three to five-year-olds and under-threes.
It sets out 69 early learning goals for the end of foundation stage, which for most children will be at the end of reception. These include children being able to write simple sentences, and read a range of familiar and common words.
But Chris Parry, chief executive of the Independent Schools Council, complained about the under-fives' framework in a letter leaked to The Times.
He said the new curriculum interfered with parents' rights to choose how they educate their children, adding that the "clumsy intrusion" was "both unjustified and unnecessary".
The Government has said that the early years foundation stage is flexible enough to support a wide range of practices.
Although parents will be able to "opt out" of the early years foundation stage curriculum, schools will not have that option. The Steiner school movement is concerned about the threat to its approach, in which reading is left until after the age of five.
In its response to the original consultation in 2006, the Independent Schools Council said that schools should be allowed to devise their own approaches.
It disagreed that the curriculum was flexible enough, and also said that the idea of outlawing all testing was unhelpful as many schools use baseline tests and tests to identify special educational needs.