Psychologist Steve Biddulph, whose latest book, Raising Boys, has been highly successful in Australia, said tests indicated that girls constantly outstrip boys. This finding reinforced his argument that many boys should start school a year later than girls to prevent them being judged asfailures before they even begin school.
Instead of using baseline testing to say that boys are deficient, it could be used to screen boys and girls who would benefit from an extra year in reception.
At Year 1 most boys simply do not have the skills needed to sit in class and concentrate on tasks, Mr Biddulph said.
"They have slower brain development than girls - they don't catch up with them until about the age of 17. At birth boys are less responsive and they make less eye contact," he said.
According to Mr Biddulph, infant teachers have known about these gender differences for 50 years, but it has been unfashionable to point them out.
He says boys' brains develop in a different sequence to those of girls. Their gross motor skills develop first, so they do not have the fine motor skills needed in Year 1.
"At that level, children need to be happy to sit at a desk and draw and write for 10 minutes at a stretch, to use scissors to cut out things, to be able to hold a pencil or crayon with reasonable control,"Mr Biddulph said.
"Boys have difficulty with those things. The boys don't necessarily have learning difficulties, they are just on a different learning timetable."
But Mr Biddulph, whose lectures in both Australia and Britain in recent years have been sell-outs, recognises that parents have problems with the concept of holding their sons back a year in school. He commented: "If a boy spends an extra year in reception class and is therefore able to do the same things as the girl in the next desk in Year 1, he will be less disaffected.
"But parents feel pressured to get their children into school earlier in Britain, even though in Austria and Germany where children don't start school until they're seven, the discrepancies between boys and girls are less obvious.
"I ask parents: 'would you rather your son was in the top one-third of the class next year or the bottom third this year?' " Mr Biddulph maintains that keeping a child back at reception level does not have the stigma of staying back a grade later in his or her school career.
In Raising Boys, he argues that this is the most under-fathered generation ever and that fathers must spend more time with their sons.
The author also encourages fathers to engage in physical rough-and-tumble activities with their sons to develop their fine motor skills and help them to learn to control their temper.
The book has sold 200,000 copies to Australian parents desperate for advice on their boys.
Its message is that fathers are critical - the idea of dad as a walking wallet is out of style.
'Raising Boys' will be published by Thorson in September.