Paying for a place in a private sixth form may not be worth the money because most of their superior A-level performance is accounted for by students’ higher ability on arrival, a new analysis suggests.
Attending an independent sixth form added an average of around 0.1 of a grade per student per subject at A level, when prior attainment at GCSE was taken into account, it says.
This is the equivalent of just one in ten students studying a single subject getting an A grade instead of a B, for example.
The analysis, published in a series of blog posts on the SchoolDash education data website, suggests that the “value added” of private education at this level may be minimal.
The same analysis also highlights that on average, in the science subjects particularly, private schools add very little more value than state schools.
And of the schools offering the most value-added in physics, maths and chemistry, it finds, state schools dominate.
But in the humanities and languages, private schools do perform better, with around two in 10 students achieving a grade higher per subject than would be predicted based on past performance.
The findings come after Ralph Lucas, the editor-in-chief of the Good Schools Guide, told TES that the independent sector could contract in the coming years, as parents turned towards rapidly-improving state schools.
He accused private schools of “lacking innovation” and being “conformist”, while praising state schools’ partnership working and willingness to try new things.
According to the annual census from the Independent Schools Council, 14 per cent of the post-16 school population now go to independent schools – double the percentage for the sector as a whole.
Many parents choose private sixth forms believing that they are the best way to maximise their child’s chances of securing a good university place.
The new analysis also comes shortly after the Independent Schools Council released research claiming that private school pupils are “two years ahead” of their state school counterparts by the time they reach 16.
The ISC commissioned report, conducted by the Centre for Evaluation and Monitoring at Durham University, compared early educational performance with students’ GCSE exam results and found that the “private school effect” was evident in every subject.
The difference was most marked in French, history and geography. However, the effect of private schooling was less pronounced in the sciences.
But the new analysis finds that much of this comparative advantage disappeared during the sixth form years.
Timo Hannay, founder of SchoolDash, writes in his analysis, which was based on 2014 and 2015 data from the Department for Education: “The overall picture seems clear: private sixth-form colleges do better at exams than state-funded ones. Although there’s considerable variation between institutions and across subjects, if we were to quantify the overall effect, we can say that it equates to roughly a grade per student per subject.
“On the whole, private sixth-forms get much better results than state sixth-forms, but most of this difference seems to be accounted for by the higher prior attainment of their students (which, credit where credit’s due, may be partly a result of the same school’s secondary education).”
He adds that there are a good number of state schools who were able to compete with, or even outperform private ones, especially in terms of academic value-added.
“So picking a good sixth form (of any kind) is far more important than simply choosing an expensive one and hoping for the best”, he explains in his blog.
“If you’re thinking of forking out £30,000 or more for two years at a private college then consider carefully what you’re getting for your money. Is there a state sixth-form that might deliver the same results? And what are the costs and benefits beyond the strictly academic?
“Private schools can offer a lot, it’s true, but thirty grand also buys a lot of private tuition, theatre trips and journeys to go out and see the world,” he writes.
‘The true value’ of private education is not monetary
Independent schools have defended their record, saying it is harder for their schools to add value in the sixth form because grades are already so high at GCSE level.
Barnaby Lenon, chairman of the Independent Schools Council, said: “Value added at all levels is outstanding, but scope for adding extra value between GCSE and A level is not as high because independent school pupils come into that two-year period with very good GCSE grades.
“If you look at the best indicator – actual A-level grades - 84 of the top 100 schools recorded by official DfE data are independent schools.”
He said it was “interesting” that the analysis noted that “discursive” humanities subjects “thrive in independent schools”.
“They require students to have the eloquence and self-confidence to make arguments on opinion rather than fact,” he said.
“This really crystallises the true value of independent schools for parents who pay for their child’s education.”
Michael Pyke, a spokesman for the Campaign for State Education pressure group, said that he thought the research showed that parents choosing private sixth forms were not just seeking higher grades.
“They could be hoping for better connections with Russell Group universities or better expertise with Oxford applications”, he said.