One in three five-year-olds leaves reception classes doing better than expected in maths and one in four exceeds goals for language and literacy, according to a survey by Durham university.
So many children are reaching the top of the foundation stage literacy scale that teachers say they are at a loss to find appropriate activities for them.
The study of 15,000 children is the first public indication of how five-year-olds did in the first national assessment last summer. This foundation-stage profile assessment comes at the end of the three-year stage and is based on observations rather than tests.
Children's abilities are graded on 13 nine-point scales such as social development and reading. They are expected to reach between point 4 and point 8. Point 9 means the child is working beyond what is expected.
In the survey, 47 per cent of pupils averaged eight or nine in the three maths scales and one in three did in communication, language and literacy.
But assessment expert Professor Peter Tymms said with so many pupils reaching the top levels, the profile is no use in identifying gifted children. Professor Tymms, of the curriculum evaluation and management centre at Durham university said the profile gave no information about progress.
"Telling a parent their child has reached level 8 is fine, but maybe the child was at that level at the start of reception," he said. "Children can make enormous progress during foundation stage which would not show up."
Jenny Simpson, head of Lymington infants, Hampshire, welcomed the profile but said it showed a need for changes in Year 1, when children begin the national curriculum. Her staff have had to invent assessment tasks for pupils who have reached the top foundation grade in reception.
When the profile was tested in 2002, the National Foundation for Educational Research found 35 per cent of children achieved all the early learning goals and 32 per cent were working beyond them.
It concluded that this meant the goals were appropriate, as most children would "be able to show positive attainment".
Every local authority has to send the pre-school results to the Department for Education and Skills by the end of this month. The results are due to be published, but no date has been announced.
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The literacy scale
Point 1 - children join in with rhyming and rhythmic activities
Point 4 - children link sounds to letters, naming and sounding letters of the alphabet
Point 7 - children use knowledge of letter sounds to read simple words
Point 8 - children attempt more complex words
Point 9 - children use their knowledge of letters, sounds and words when reading and writing independently