Teenagers are today receiving their long-awaited A-level results, with around one in four entries expected to receive top grades.
Boys are likely to outperform girls again in terms of A*s, with one expert suggesting that they could also close the gap with their female classmates at the A grade boundary.
Last year, a quarter (25.8%) of A-level entries across England, Wales and Northern Ireland, were awarded an A* or A, compared to 25.9% the year before, and 27% five years ago.
Official figures show that 8.5% of UK boys' entries were given the highest result of A*, compared to 7.7% of girls' entries, while there was just a 0.3 percentage point gap at A*-A, with girls ahead on 26%.
This year's results mark a key step in major reforms to A-levels introduced by government in recent years, including a move away from coursework and modular exams, as well as a significant decision to separate AS-levels to form standalone qualifications.
This shake-up, which applies to England only, has led to a 42% drop in AS-level entries this year, and school leaders today raised concerns that the reform has "sounded the death knell" for qualifications that were traditionally popular with many students and universities alike.
A snapshot survey of around 170 heads in England conducted by the Association of School and College Leaders (ASCL) found that around two-thirds (65%) have cut the number of AS courses they offer in the wake of the Government's reforms, while 86% said they expect to remove AS courses in the future.
ASCL general secretary Geoff Barton said: "It is increasingly clear that government reforms have sounded the death knell for AS-levels.
"AS-levels allowed students to study four subjects knowing they would all count towards a qualification, either an AS-level or a full A-level.
"They were intended as a way of broadening the curriculum and were valued by students, employers and universities."
He added: "The great benefit of the old system was that it gave students a broader range of knowledge and allowed them to keep their options open for longer.
"The decision to decouple these qualifications was an entirely unnecessary reform which is narrowing the curriculum and reducing student choice."
Under the previous system, sixth-formers typically took four subjects in their first year of the sixth-form, before deciding which three to continue with to full A-level in their second year.
AS grades were often used by universities in making offers to applicants, as they were an indicator of a student's final A-level results.
The move to decouple AS-levels proved controversial at the time it was announced, with universities - including Cambridge - headteachers and MPs among its critics.
Ministers argued that universities learn little more from knowing teenagers' AS-level results in addition to GCSE grades and insisted that the reform should not affect university admissions.
This year will also see the first A-level grades given in 13 subjects which have been reformed - art and design, biology, business, chemistry, computer science, economics, English language, English language and literature, English literature, history, physics, psychology and sociology.
These changes mean that students sit all exams at the end of the two-year-courses, rather than throughout, with less coursework.
The Government's exams overhaul could benefit male sixth-formers, according to Professor Alan Smithers, director of the Centre for Education and Employment Research at Buckingham University.
He told the Press Association that major reforms to A-levels back in 2000 - which saw a swing towards pupils sitting exams throughout their two-year courses - had benefited girls. Now that this being reversed, it may advantage boys, particularly in terms of top grades (A*-A).
Experts have previously suggested that girls tend to respond to modular courses, as they can apply themselves throughout the course, working towards specific modules or coursework, whereas boys are more likely to revise in the weeks before a final exam.
''I think cutting to the chase, what happened when A-levels changed from end-of-course to modular, which led to a big gap opening in favour of girls, suggests that the reversion to end-of-course examinations will lead to a narrowing of the gap.," Prof Smithers said.