By Angela Harrison
BBC education reporter
Girls are said to produce better course work
Scientists are excited by the rise in popularity of science GCSEs and experts say the tide could be turning for boys, who have long been out-shone by girls.
More teenagers are doing physics, chemistry and biology as separate subjects, data for England Wales and Northern Ireland shows.
And boys have slightly narrowed the gap with girls and beaten them at maths for the first time in more than a decade.
Experts predict the end of course work will bring higher grades for boys.
Course work - or rather the lack of it - is said to be one of the reasons boys are fighting back.
Maths dropped its course work two years ago and boys' maths scores have risen. They beat girls across all the grades this year.
Course work is on the way out for many other subjects from this September and is being replaced by projects done in school under supervision.
Dr Mike Cresswell, head of the AQA exam board, said this was this first time that boys had done better at GCSE maths since 1997.
He said: "The obvious speculation is it reflects the removal of coursework from GCSE maths.
"It's well established that girls outperform boys at coursework."
Dr John Dunford, general secretary of the Association of School and College Leaders (ASCL), said: "Boys have overtaken girls at GCSE maths, coursework having been abolished two years ago. It clearly shows how the type of assessment directly affects achievement.
"This suggests that next year, when coursework is reduced in many other subjects, boys' achievement will catch up with girls."
He added: "Girls work more consistently over the two years and boys prefer to learn things at the end."
Scientists meanwhile are wondering if the tide is also turning for them, with an increase in students opting to study chemistry, physics and biology.
The increases are encouraging: 18% in biology, 20% in chemistry and 21% in physics (between 15,000 and 16,000 extra students in each subject) in a year when GCSE entries overall fell by 3.5%.
Dr Hilary Leevers, from Case (Campaign for Science & Engineering), said: "We are delighted that entries into triple science GCSEs are increasing and by such large amounts."
She said take up of the separate sciences had been in a "downward spiral" in the 1990s but that this year's figures on GCSES, plus signs that more students opted for sciences at AS-level, were "very positive news".
However, much of this year's growth in the separate sciences has been in the independent sector and in selective state schools.
Case says only 32% of state schools entered students into triple science in 2008.
Case believes the exams give a greater grounding in science in preparation for A-level and university study than the alternative - which is studying the subjects together in science and additional science.
Dr Leevers said: "Case has long campaigned for triple science to be available to all students and, as more are now being offered triple science, we are pleased and relieved to see that students are flocking to it".
Linguists meanwhile are less happy with the trends emerging.
The total number of students sitting a language GCSE this year was down by 4.1%. As the number of students taking GCSEs was smaller this year (down 3.56%) a drop might be expected, but the fall in languages was greater.
French fell most, by 6.6% and German by 4.2%. Spanish remains stable however.
Dr Anne Davidson Lund, from Cilt, the National Centre for Languages, said: "We are very disappointed to see a continued decline in the take-up of GCSE languages.
"There are energetic efforts in so many schools across England to motivate language learners but this is not showing yet in these exam results."
However, Dr Davidson Lund said a Cilt survey showed a third of state schools had introduced new courses and teaching approaches which had led to "improvements in pupils' attitudes and in take-up of languages".
Language qualifications other than GCSEs also continued to prove popular.