Calling all education data nerds! Can anyone help me make sense of these slightly weird OFQUAL stats? (Comparing high grade GCSEs in grammar and private schools)

Will the independent school figures also include numbers from private exam centres that take elective home school students, and those doing resits perhaps? Might explain some of the discrepancy in English and Maths. I know my niece failed maths multiple times and ended up taking her GCSE in a private centre. Most of these students would be aiming for a basic pass, therefore diluting the stats? (The resit students, not necessarily EHE ones, although would be interested to know how they fare overall)

Not this data, it includes all students entered, regardless of age.

*Reply to puffyisgood.

The difference could also be that selective schools e.g. grammars may not enter pupils for GCSEs if they are unlikely to achieve a good grade in a non core subject. This would affect History more than Maths / English where everyone would be entered.
Taking a GCSE subject in Maths a year early in Y10 e.g. Maths may also have an effect on the data as it would decrease the number of Y11 pupils achieving the grades which is recorded in the data.

Well I was the first poster and I didn’t mean what you are suggesting and no where did I post that. When I posted I was well aware they weren’t counted at all and the results would be skewed towards the lower achieving independent schools as I posted in my follow up reply to LouisCatorze.

which makes it sound like you thought we only suggested IGCSE may at least in part be a factor because we thought the data included IGCSEs

The usual issue is that the data doesn't count IGCSE, so we end up with schools that take IGCSE scoring a 0% pass rate. As per the suggestions from the first few posters on this thread, which is what I was disagreeing with.

You posted I don't think it's about IGCSE because the data only includes centres which have entries in that subject group. which makes it sound like you thought we only suggested IGCSE may at least in part be a factor because we thought the data included IGCSEs. Hence my post, because that isn’t what we suggested.

I know it might not be the same which is why I posted I don’t know about this specific data set.

What we are saying is if the higher performing independent schools tend to sit IGCSEs

I have said that this sample is very small and there is no indication of whether it is representative. I don't know what proportion of higher performing independent schools sit IGCSE, but it is certainly clear that the ability spread in the sample in this dataset is far wider than that of the grammar schools in this dataset.

but normally independent SS are categorised as SS rather than independent for statistics purpose e.g. on the government school performance tables.

Yes but the classification here is self-reported, so may not be the same.

I think you have made the same mistake Puffyisgood made, we know the statistics only include those who have entered GCSE. What we are saying is if the higher performing independent schools tend to sit IGCSEs, thus for those subjects aren’t included in the statistics, the independent school statistics are skewed towards the lower performing independent schools, therefore they will have lower results and aren’t comparable to selective state schools.

I don’t know about this specific data set, but normally independent SS are categorised as SS rather than independent for statistics purpose e.g. on the government school performance tables.

And you really need to remember that there are a lot of private schools that are not academically selective - eg there are a lot of Islamic/Jewish schools that are private, non selective and have very little attention paid to secular subjects.

I wondered if it might be a little clue that, perhaps, kids in grammar schools are, on average, slightly more academically able...?

Well yes, grammar schools are, by definition, academically selective, whereas independent schools are not necessarily.

You can see the impact of this more easily if, instead of looking at the 7+ score, you look at the 4+ score.

For maths, which has to be taken by every pupil, grammar schools have, in 2019, 99% of their pupils getting a 4 or above in maths, as you would expect. In independent schools, this is 80.9%. If 1 in 5 independent pupils are failing maths, but only 1 in 100 grammar pupils, this suggests that grammar pupils are indeed more academically able as a cohort and would explain the much higher proportion of top grades.

I don't think it's about IGCSE because the data only includes centres which have entries in that subject group.

The number of centres is very small, however. This is not national data. I'm not sure how they have been selected so may not be representative.

There is also an issue that the type of centre is self-reported. Quite a few special schools are independent - would they have classified themselves as a special school, or an independent school? This could affect the data.

It will be the igcse effect. If a big chunk of the high performing privates don’t have gcse English results you only see the low performing ones - which definitely will be below grammar.

All the schools doing igcse will be getting a very high proportion of 7+ at English (think it’s close to 100% at dc’s school) but none of these are showing in the stats.

I think the gap will also reflect the fact that ALL grammars are academically selective.
Not all private schools are as selective, and some are not academically selective at all.
This is a good illustration of why the endless state vs private threads on here can never result in a clear cut answer. Every school under consideration - whether state or private - needs to be compared against each other, as well as considering the needs of the individual child.

you're right, I didn't read the full post, you're saying that more selective private schools are disproportionately likely to sit IGCSE, that's probably right.

there might be some other clues from not looking just at the gap but at the absolutes, eg the private schools' maths score might not be so anomalously low as the grammars' maths score is anomalously high.

@Iamnotthe1 my point was more that parents believe they are getting both in the private sector. Whether they do actually get both is a different matter entirely though.

I think you have misunderstood others’ posts, no one has said it shows the % of all students in Y11 (not that GCSEs are only taken by Y11 pupils). If the higher performing independent schools tend to sit IGCSEs, thus for those subjects aren’t included in the statistics, the independent school statistics are skewed towards the lower performing independent schools, therefore have lower results and aren’t comparable to selective state schools.

@LouisCatorze another reason is in some subjects IGCSEs don’t have NEA or it is optional whereas the GCSE does.

Do you really believe parents are just paying for environment rather than quality of teaching in independent schools?

Yes, absolutely. I can't speak for secondary schools that much but, at a primary level, yes. I've worked with both private and state schools and, whilst there is a mix of quality in both, the weaker teachers I've seen are definitely in private. You're paying for the class sizes, better access, improved facilities and potential connections for future education/work.

@TurquoiseSeaglass I mean the same thing. They both demand more because there's a lot at stake and they have chosen something either difficult to get into or expensive.

I think the quality of the education is impacted more by the background/drive of the kids than anything else. Grammar and independent schools get good results because the kids want to work hard and learn AND this makes teaching easier so the tuition is automatically better. Add in selecting the brightest kids and you've got a perfect recipe for good results!

I don't think it's got much to do with IGCSE's, I'm pretty sure that all the stats show e.g. the percentage of candidates in subject X who get top grades in subject X rather than the percentage of all pupils in year 11 who got top grades in subject X. You can see this in the results for relatively obscure subjects, e.g. there's no way that 72% of all grammar pupils are getting a top grade in "classical subjects".

If the difference was just in maths and maybe a couple of other STEM subjects my first instinct would be to put the difference down to grammars being increasingly dominated by the kids of Indian families who take STEM way more seriously than other stuff and who in terms of written English maybe don't always have perfect fluency. But English is one of the other big outliers. I guess maybe maybe when it comes to the science subjects there's a different culture in terms of selecting which students sit triple/combined etc science.

Overall I suppose it comes down to the difference in budget per head [roughly double on average at private schools, though plenty of the extra goes on non-academic stuff] vs the amount of selection [the average private school is barely selective at all, and in the few grammar areas may even be negatively selective, in terms of only pulling in kids who both failed the state 11+ and whose parents were up for paying fees], it looks like the two often balance each other out but in a few subjects selection is more important than teaching budget. The very highest performing schools, as the league tables etc show us, tend to be the ones which both are very selective and have exceptional budgets.

Thanks @Comefromaway.

The private school that ds attended for a short time said that it felt that IGCSE were better preparation for A level. When the new 9-1 GCSE's came in they had a year or two of seeing how they went then I believe they swopped back for some subjects.

I am on a forum for drama teacher and know IGCSE is popular for that subject as marking criteria etc are more transparent.

Why do some private schools choose IGCSEs over GCSEs, out of interest?

I'd say it's the grammar school parents who truly place a value on education and the private schools ones who are demanding and pushy.