By 1995 girls scored on average 8 percent more than boys in the proportion of A*- C grades gained at GCSE. Girls are ahead in most of the traditionally `male' subjects, such as physics and chemistry, although the gap is much narrower than in subjects like English where girls have traditionally done well. Only in one subject, biology, do boys have a substantial lead.
So concerned have some in the education world become that they are looking for ways to help boys `catch up'; one school in Oxford has even gone back to teaching boys and girls in separate classes.
But with men still taking most of the top jobs at the end of the day, do boys really need more help at school? Patricia Murphy, director of the Centre for Curriculum and Teaching Studies within the OU's School of Education, has been studying the differences in the ways girls and boys perform in the education system since the 1980s.
A former secondary school science teacher, Patricia says that while there is some truth in the notion of boys' under achievement at school, the full picture is more complex.
"Girls have always done well in certain subjects such as English, but it's true that they are now out-performing boys at GCSE in most subjects, even science." This is an overall picture, of course; there are some boys doing very well, and some girls not.
"But at post-16, the picture changes. At A-level boys, overall, perform relatively better than girls."
What research by Patricia and others suggests is that boys and girls approach the task of learning differently, and these differences may work either to their advantage or disadvantage, depending on the learning situation.
The switch from the old GCE/CSE to GCSE, which measures a broader range of achievement and makes more use of assessment, favoured the female approach.
"In the English GCSE, for example, there is a lot of value put on the descriptive, narrative, empathetic and personal," says Patricia.
"At English A-level, on the other hand, what is required is a much more precise, objective approach to analysing text - a strong point of view, argued concisely. "The first approach reflects the girls' preferred style of writing and choice of reading matter; the second that of the boys.
The differences between girls and boys, observed by a number of researchers, begin very early. One recent study of how pre-school children tackled jigsaw puzzles, found that the girls were far more likely than the boys to ask for help with the task. And, significantly, adults shown videos of the children had the impression that the boys performed the task better.
Girls' success was more likely to be put down to `luck' rather than skill. In fact there was no difference between the girls' and boys' performance. Such interpretations of children's behaviour, the researchers suggest, are likely to influence how the children see themselves, and what they think is expected of them.
Research also shows that when boys get feedback it tends to be about their behaviour, rather than their work; for girls the reverse is true.
By the end of primary school, girls are generally conforming more, and more anxious about doing what the teacher wants and working towards the goals of the school. Boys, on the other hand, are less bothered about such things, probably because they have higher levels of confidence.
There is quite a large amount of research to suggest that girls and boys faced with the same situation, typically pick up on different details.
Surveys conducted by the APU (Assessment of Performance Unit) in the 1980s on performance in practical tasks in science and design and technology, revealed that girls tend to focus on aesthetic details, such as colour and sound, and to empathise with users' needs.
In contrast, boys tackling the same task are more interested in mechanical and structural issues. Both approaches are valid, but both are incomplete.
Patricia and her co-researcher Jannette Elwood of the Institute of Education note in their most recent paper, Gendered Experiences.
"When people observe, there is always more information than they take note of. Observation is fundamentally a selection process. Students and teachers alike need strategies that help them `see' the way they filter and select data in different circumstances."
Whether these differences between the sexes have a genetic basis, or are formed at an early age by the social expectations of those around, is still a matter of debate. What schools must do is to appreciate that these differences have consequences for learning, and take account of this in planning lessons and assessing boys' and girls' performance.
"Research shows, for example, that girls are more likely than boys to engage in collaborative talk, which benefits their learning. So when girls are playing with dolls, acting out social situations, there is an awful lot of talking going on.
"Whereas in boys' play situations, there are often not the same opportunities for talk between people. But boys could be encouraged to the same - not by giving them dolls to play with, but in a situation where they were, say, organising their knights for a battle.
"Likewise with reading, more work needs to go into finding a wider range of reading materials that reflect boys' interests as well as girls'."
Patricia is concerned though, that the focus on underachieving boys could rebound on the girls. While action is needed to help those boys who are falling badly behind and in danger of ending up as an alienated, unqualified underclass, at the end of the education system young men are still coming out on top.
"We do need to be worried about boys at the bottom of the class, who never achieve a basic level of competence. But that should not make us complacent about the girls."