Calling all primary heads. Do you want to raise achievement with no extra effort? It’s simple - admit to your schools only girls born to middle-class parents in the autumn.

Statistics confirm that girls do better than boys, that children from leafy suburbs perform better than those from more deprived areas and that autumn-born children do better than those born at other times. Summer-born boys on free school meals should be avoided at all costs.

So what can the ambitious head do? Put aphrodisiacs in the local water system every January and February? Move the school to a more leafy setting? Make sure local males of reproductive age wear tight underpants (or is it the reverse?). We have no control over the gender, date of birth or socio-economic status of our pupils, but we could look at the way we admit children to reception classes.

My school, in common with many other primaries, has three intakes into reception. The oldest children, born between September and Christmas, enter in September, those with birthdays before April enter in January and the rest after Easter. This is an arbitrary system that takes no account of a child’s readiness for school and which disadvantages the very youngest.

All teachers know summer-born children need the most support and have the highest level of special needs. The reasons are obvious - they’re younger than their classmates, a disadvantage compounded by the little time they have spent in school. These babies are launched into Year 1 and the full horrors of the national curriculum after only one term. In Year 2 we expect them to achieve the average level 2 (now raised to level 2B) in their SATs. By then they will have had fewer than seven terms in school, against nine for their older classmates. This difference continues all the way through their education.

So, what is being done about it? Not a lot. Some schools have early admissions into reception and take all the children in one dollop in September. But many schools, including mine, still operate the traditional three-term entry. It is a historic pattern. Are we continuing to operate an ancient system because it’s good or because it’s always been done that way?

Children vary in their readiness for formal schooling. But age is too crude a measure - some summer-born children may be raring to go and ready for GCSEs when they are just four, and some older children may not be ready for “big” school until they are five-and-a-half. In this age of parental choice, it surely makes sense to allow parents to choose at which point during the reception year their children are ready for school.

If we do offer a reception place to all children in the September following their fourth birthday, we must make sure these early admissions classes are adequately staffed and resourced. They must allow for learning in the broadest sense rather than being academic hothouses. You can’t make these children any older, but you can give them equality of time in school.

The complications of reception classes with three intakes do not stop with the educational value offered to the children. As a headteacher I have to keep a classroom idle (continuing to heat, clean and maintain it) for two-thirds of the year awaiting the summer group. The Government is rightly concerned with surplus school places. Has anyone counted the cost of leaving all those classrooms empty? If my governors and I chose to be so wasteful with our resources, we would soon be hauled over the coals.

And staffing is a nightmare. We have to find an extra teacher just for the summer term, only to discard him or her in autumn before finding another the following year.

Now that we must keep infant class sizes lower than 30, we have an additional headache. Children do not come conveniently packaged in groups of 30, and even if they did, they do not come in equal groups during the year - your three-term intake could be eight in the autumn, 15 at Christmas and seven after Easter. I will do my best to ensure no child has three teachers during the course of the year, but it is inevitable that some will have two.

As yet, no parents seems to have cottoned on to the fact that their summer-born child is being deprived of two terms’ worth of education. When, I wonder, will the parent of a summer-born child sue the LEA or the Government for failing to provide equality of education opportunity for his or her child?

I am not joking.

Cathy Byrne is head of Danepark primary school in Hull