A girls' boarding school today topped an A-level league table for the fifth year in a row.
Wycombe Abbey in Buckinghamshire took the first spot again after pupils racked up a string of A* and A grades.
Each student gained an average combined A and AS-level UCAS point score of 540.
This is equivalent to almost four A* A-level grades each.
In total, 85 sixth-formers achieved 284 A* and A grades between them.
Wycombe Abbey, a private school charging up to £10,650 per year for boarders, and £7,990 for day pupils, teaches girls aged 11 to 18.
It has been consistently at the top of a league table of private schools for five years.
The table, based on data provided by the Independent Schools Council (ISC), reveals that Concord College, a boarding school in Shropshire catering to boys and girls aged 13 to 19, was second nationally for A-level results this year.
Principal Neil Hawkins said the college's students had worked "incredibly hard" for their grades.
He said that behind the "bald statistics" there had been some individual "triumphs" with students over-performing.
Mr Hawkins put the school's success partly down to the environment created by a boarding school.
"There's that opportunity to create a community where there's the expectation of success.
"That certainly is what we're able to do here."
Concord's 149 A-level students achieved an average AS and A-level UCAS points score of 501, and between them notched up 204 A* grades and 211 As.
Mr Hawkins said A-levels are "something I believe in very much".
"I think it's a fantastic qualification which allows students to specialise."
He added that he was in favour of the move to introduced the A* grade at A-level because "it has given a benchmark which has been very useful at the top end".
Overall, private schools saw a drop in A-level results this year, reflecting the national picture.
Some 51.4% of A-level entries from privately educated pupils achieved at least an A grade this year, down from 52.9% in 2011.
And 17.99% of fee-paying school entries were given an A*, down from 19.07% last year.
The ISC said that its preliminary findings showed that 6.1% of its candidates, around 2,036 pupils, were awarded three or more A*s.
National A-level results, published by the Joint Council for Qualifications last week, showed that across England, Wales and Northern Ireland 26.6% of all entries were awarded an A or A*, down from 27% in 2011 - a drop of 0.4%.
It is believed to be the biggest fall on record for A-levels.
Some 7.9% of exams have been awarded an A*, a drop from 8.2% last year.
The ISC published results from 492 schools, taking a range of qualifications, including A-levels, the International Baccalaureate (IB) BTecs, the extended project qualification and the Cambridge Pre-U examination.
The Abbey School in Reading scored highest in terms of the IB, with 14 pupils taking the qualification achieving an average UCAS points score of 575.
Tim Hands, Master of Magdalen College School in Oxford, claimed there had been "grade deflation" in both A-levels and GCSEs this year.
"This year's A-level results apparently provoked little controversy, whereas this year's GCSE results have provoked much more comment," he said.
"This is surprising since the same principles seem to have been behind both sets of results - this principle is grade deflation.
"It would be easy to understand consistency in grade boundaries, it is more difficult to justify grade deflation.
"What one generally wants to do with people, especially young people, is to encourage. Is it a good form of encouragement, without warning, to shift grade boundaries in such a way to leave young people disappointed and feeling their efforts may not have been worthwhile?
"People will look for what's behind the shift in grade boundaries. Some headteachers may take a good deal of persuading that this is not the result of political influence. It may take a lot to persuade some people that in this matter the Secretary of State has not been putting the Gove in governance.
"A-levels and GCSEs should be an academic not a political matter."
Education Secretary Michael Gove has denied there was any political interference in exams.
Speaking as the GCSE results were published on Thursday, he insisted that any changes in grades were the result of "independent judgments made by exam boards entirely free from any political pressure".
He said the reason some pupils had poorer GCSE results than expected was partly down to a change in the system which meant their exams had been split into units and modules this year.
Asked about concerns that English papers were marked too harshly, Mr Gove told BBC News: "Yes, the number of As and A*s has fallen, but the number of Bs has increased, the number of Cs has fallen and the number of Ds has increased.
"That is a result of the independent judgments made by exam boards entirely free from any political pressure and I think that the various chief executives of the exam boards, and indeed the chief executive of the regulator Ofqual, have made it clear that these decisions have been made because the exam boards and the regulator have sought to ensure this year, as every year, that exam results are comparable over time so that we can all have confidence in the examination system."
Magdalen College School was fourth in this year's A-level league table of private schools, with sixth-formers achieving an average AS and A-level Ucas points score of 482.
Judith Carlisle, head of Oxford High School GDST, which came third in the table, said: "The girls have tremendous fun while they're learning and they always aim high.
"I'm delighted that their sparkle has turned into A*s. Well-deserved stellar results!"