Children born in the summer suffer academically for their entire school life compared with their older classmates, researchers claim. The age gap affects GCSE and A-level results and can even result in pupils being wrongly classed as special needs.

The Institute for Fiscal Studies has called for a radical change in educational policy on the strength of its extensive study of the impact of age on learning. It wants schools to take pupils’ ages into account when marking tests and to let pupils sit exams when they are ready.

The institute report says: “August-born children are, on average, being penalised simply because of an unlucky birth draw. This is not acceptable and steps should be taken to eliminate this penalty.”

Over two years the institute studied the exam results of more than two million state-educated children aged 5 to 18. The most striking difference was at the age of 7, when there was a 33 per cent gap in attainment for the youngest children (born in August) and their oldest classmates (born in September the previous year).

Experts had believed that children born in the summer caught up with their older peers by the time they reached secondary school. But the institute’s data show that younger pupils achieved lower results even at 16 and 18, which affected their chances of progressing to higher education and ultimately their career choice. “The gap steadily decreases between age 7 and age 16, but remains evident even at the end of compulsory schooling, so it may potentially be affecting decisions over whether to stay on at school beyond then,” the report says.

According to the data, 55 per cent of girls and 44 per cent of boys born in August achieved at least five good GSCEs compared with 60 per cent of girls and 50 per cent of boys born the previous September.

Some teachers appeared to misconstrue age-related poor performance as evidence of special needs. At age 11, girls born in August were 72 per cent more likely to be classed as special needs than their oldest classmates. For boys the figure was 46 per cent.

Delaying a younger child’s start at school did not help and could have a negative effect on his or her progress. “In general, August-born children are slightly better off, and certainly no worse off, if they start school in the September rather than in January or April as happens in some local education authorities,” the report says.

The authors suggest that schools introduce flexible testing, so pupils can sit exams when they are ready, as well instructing teachers to take account of pupils’ ages when marking exams. They also recommended giving summer-born children free nursery care earlier.

The report highlights that the issue of age, and its relationship with test scores, does not features in the teacher training. “This means that newly qualified teachers (and possibly as a consequence the parents of young children) may not realise how big an impact relative age has on test scores. Raising awareness of this issue seems to be a vital first step towards any potential tailoring of classroom tuition towards children of different ages.”

Claire Crawford, one of the report’s authors, said: “There is concern that the difference at GCSEs could discourage or prevent some children from carrying on post16, affecting their whole lives.”

She added: “We didn’t have information about private schools. There is some evidence to suggest there may be fewer August-born children from higher socio-economic backgrounds in the state sector.”

— Parents should spend at least ten minutes every day reading their children a bedtime story to instil a love of books from an early age, Ed Balls, the Schools Secretary, said yesterday. His announcement precedes next year’s National Year of Reading. “Let’s make a start now,” he said.

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