The number of entries awarded an A or A* has remained level, the first time since 1997 that the percentage of top grades has not increased.
The gender gap in exam results increased slightly, by 0.5%, with 71.3% of girls' entries awarded at least a C grade compared with 62.4% of boys'.
There was a two percentage point drop in the proportion of entries awarded C or higher – the biggest fall since GCSEs began in 1988.
Overall, the results - received by 600,000 teenagers - showed a rise in the number of top grade A* to C grade passes with almost seven out of 10 entries awarded at least a C grade.
The national figures, published by the Joint Council for Qualifications (JCQ), also show that the gender gap narrowed slightly this summer, with 73.1% of girls' entries awarded at least a C grade, compared with 64.7% of boys'.
The number of pupils taking academic subjects such as English and physics took a surprising fall this year, as the latest A-level exam results revealed a continuing decline in the proportion of entries awarded the highest grades.
A-level results are out and the 2014 figures show that despite a rise in the proportion of exam entries awarded an A*, the percentage of students achieving A* to E dropped to 98% from 98.1% in 2013.
The figures for England, Wales and Northern Ireland show that the gender gap increased slightly this summer, with 71.3% of girls' entries awarded a C grade or above, compared with 62.4% of boys'.
Along with Palette, the Undergraduate Challenge also recognized NoMor (Chiara Vallini SEAS'17, Caroline Chiu SEAS'17, HaeSeong Kimg SEAS'17, John Mavroudes SEAS'17 and Walid Rahman SEAS'17) and Pencraft (Derek Netto SEAS'17) for their entries, awarding the teams $15,000 and $10,000, respectively.
Kings College school, an independent boys school in Wimbledon, south-west London, achieved spectacular results, with 84% of its entries entries awarded A*, while 97% of all grades achieved by the class of 149 gained A* or A. "I have always believed boys can do incredibly well with the right motivation and inspiring teachers who know what makes boys tick," said Andrew Halls, the headteacher.
