Barnaby Lenon, Chairman of ISC, said: "To see an increase in independent school grades across the board is excellent news and testament to all those working hard in our schools - and of course to the young men and women who sat the exams having built towards them for a number of years.
"Set against a decrease in numbers nationally and in an environment where there are efforts to halt grade inflation, this is particularly impressive."
Julie Robinson, ISC General Secretary, said: "Once again, the value of an independent education can be seen through the achievements of the students in our schools. GCSEs might not be the most popular of exams - and some commentators have questioned the validity of public examinations at this point in a student’s education. However, our schools put much emphasis on the core subjects of English, maths, sciences and languages, much-prized by universities and employers, so these exams continue to be a formative stepping stone for our pupils."
On top of all other aspects of independent school life, visible recently with the sporting successes of our alumni in the Olympics, these results show there is great strength and continued value in independent education. - Julie Robinson
At A-level, almost half of all independent school entries received either an A* or an A this year. At 48.7%, the A*/A percentage is nearly double the national average of 25.8%.
The percentage of students achieving at least ABB - a set of results desired by many of the top UK universities - remains at 55.5%.
Barnaby Lenon said: "A concerted effort to halt grade inflation in recent years has seen the top grades both nationally and in independent schools level off and fall slightly, so it is encouraging to see the headline A* and A figure remain solid.
"Of particular note is the increase in students achieving ABB grades, which will see many of them moving on to the university of his or her choice, a high number to the top institutions.
"Importantly, the actual grades achieved remain impressively high. ISC schools focus strongly on the 'facilitating' subjects which are much prized by top universities. In 2015 our schools had record levels of entry to Russell Group universities and we expect this trend to continue"
Julie Robinson said: "The annual exam results each August remind us all that the academic side of school life is a top priority and that the grades achieved help pave a foundation for much that is to come for many young people.
"On top of all other aspects of independent school life, visible recently with the sporting successes of our alumni in the Olympics, these results show there is great strength and continued value in independent education."
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