Out of curiosity I went to visit a local independent school a couple of years ago on their open day. I'd been past the school many times, but never been inside. What an eye-opener. My most recent experience of (state) schools was the one my daughters went to - youngest now 22, so it's a few years ago but not many. The independent had facilities I could never have imagined. Acres of sports fields, fantastic equipment (especially for Design Technology which seemed to me to come from the space age), recording studios for music and so on. I know it's the quality of the teaching that really counts, but even though my daughters' teachers were by and large pretty good, what more might they have been able to achieve in such conditions? And what does being surrounded by the best of everything say to the pupils about how they are valued? Something rather different to the message my daughters got from the seen-better-days offerings of their own school. Then there was the school day. Clubs from 8.00 in the morning till 8.00 in the evening, with more or less everyone expected to stay until 5.30 at least - three afternoons a week were for sport and physical activities with normal lessons re-starting at 4.00. The range of 'enrichment' activities including all the PE-type options was astounding, really something for everyone including the less sporty youngsters. Supervised homework available for those (or their parents) who wanted it. And the number of trips abroad had to be seen to be believed - geography trips to Iceland, language trips to France, Spain, Germany, Italy, China, physics trips to Switzerland (large Hadron collider anyone?), classics trips to Greece and Turkey, sports fixtures in the USA and Canada, and so the list went on. These kids were expected to travel the world. And at the open day much was made of their alumni association, and how it could be used to support pupils and ex-pupils and ease their way into the professions of their choice - very old-school-tie.
The school in question was charging £9000 a year. I don't know how that compares with fees across the sector, but going by this thread I think it's fairly middle of the road - not cheap, but not the most expensive either. Now, combine all the 'outside school' factors people have talked about already - e.g. the school can simply say no to the pupils it doesn't want, and of course that makes one hell of a difference. Then factor in everything the school has going for it that state schools simply can't provide. No wonder pupils at the school do so well. How could any state school possibly compete? And yet my daughters, without all of that, got the exam grades they needed to go to the universities they wanted. Hooray for the state school teachers who supported them, despite not having the advantages of the independent sector is all I can say.