As teenagers across the country anticipate their GCSE results this week, concerns were raised today that the exam system is in "disarray" and in need overhauling.
Experts are predicting another bumper crop of results this year, with the possibility that almost seven in ten exams could be awarded at least a C grade.
Last summer's results were another record-breaking year, as the A*-C pass rate rose for the 22nd year in a row.
More than two thirds (67.1%) of entries were awarded at least a C grade, while more than a fifth (21.6%) received an A or A*.
Some 7.1% of entries alone gained a coveted A* grade - this proportion has more than doubled since the grade was first awarded in 1994.
Nansi Ellis, head of education policy at the Association of Teachers and Lecturers, warned: "The UK's exam system in in disarray.
"It consistently fails the 40% of young people who do not get five good GCSE passes and leave school feeling failures.
"But even those who achieve a string of A*s are not well served by GCSEs; they are taught to pass tests, rather than encouraged to learn skills and leave bored by endless testing.
"And crucially our exam-obsessed system is not designed to develop the softer skills, such as creativity, initiative, problem-solving, reasoning, and team-working, that young people need for higher education, work and their future lives.
"The Government desperately needs to end its obsession with exams and agree an assessment system that meets the needs of today's young people."
Professor Alan Smithers, of the Centre for Education and Employment Research at Buckingham University predicted that around 7.5% of entries will be awarded an A* this summer, and above 22% will get an A* or an A.
He said there were a number of reasons for the consistent rise in the proportion of entries awarded top grades.
"It's the structured questions, I think it's the teachers know now what the exam boards are looking for in answers, it's the importance of the results to the schools."
Secondary schools are ranked on the proportion of pupils getting at least five C grades, including in English and maths in annual league tables.
Prof Smithers predicted: "I would have said probably above 22% will get A* or A this year, with the proportion of A* grades perhaps getting close to 7.5%. A* to C grades might be getting around 68%."
Last year, there was a slight drop in the number of English entries being awarded at least a C grade, down to 62.7% from 62.9% in 2008.
Prof Smithers said the results for English and maths are "the best indication of what's happening in the school system".
He added: "It should be going up a bit faster given the investment in primary schools and National Strategies should be filtering through now."
Around 750,000 teenagers in England, Wales and Northern Ireland will receive their results on Tuesday.