We reposted this blog on X in March 2024 to mark International Women’s Day. Please feel free to comment below sharing your experiences and reflections on gender balance in physics.

Those of you who have followed my previous posts will know that I’m interested in the choices that students make at Key Stage 5. And – having spent many years at the Institute of Physics before joining Datalab – I’m particularly interested in A-Level physics.

Anyone who knows anything about A-Level physics probably knows it has an issue with gender balance (among other diversity issues). Just 22% of those who took the subject in 2021 were female. Only computer science had a lower proportion of female students.

But back at the Institute of Physics, we produced research showing that girls who attend single sex schools are far more likely to go on to study A-Level physics than those who attend mixed schools.

One possible explanation for the higher proportions in single sex schools choosing physics is that those taught in a single sex environment are less likely to see some subjects as being ‘for boys’ or ‘for girls’.

On the other hand, physics tends to be associated with high prior attainment. And pupils in single sex schools have higher attainment, on average, than those in mixed schools.

So is the higher rate of progression really anything to do with the single sex environment?

The situation

Let’s take a step back and see just how big the difference in progression is.

Of those female pupils who completed KS4 in a state-funded mixed school in 2019, 1.9% went on to enter A-Level physics two years later. This compares to 5.8% of girls in state-funded single sex schools.

So a fairly large difference – but then again, girls who went to a single sex schools are more likely to take any Level 3 qualification than those who went to mixed schools – just 56.9% of those in mixed schools go on to enter an L3 qualification, compared to 77.3% of those in single sex schools.

Let’s see how physics compares with some other subjects. I’ve included subjects that girls in single sex schools were more likely to access, with at least 1,000 entries from girls in mixed schools.

The difference in progression to physics is actually relatively small compared to some of the other STEM subjects, and even some subjects that tend to be more popular with female students, like psychology and English literature.

And, in yet another blow to my theory to pupils in single sex schools feel freer to make less gendered choices, boys in single sex schools are also more likely to choose STEM subjects and economics than those in mixed schools. 15.5% went on to enter A-Level physics, for example, compared to 7.9% of those in mixed schools.

Again, I’ve included subjects that boys in single sex schools were more likely to access, with at least 1,000 entries from boys in mixed schools.

Does attainment explain it all?

In an earlier post, I looked at what we can deduce about school entry requirements for different KS5 subjects. I found that almost all (96.9%) of those who entered A-Level physics held a grade 6 or above in either GCSE physics, or the equivalent in double science GCSE.

Pupils who do not achieve a grade 6 or above are unlikely to be able to progress. And there is a far lower proportion of these pupils in single sex schools. Among female pupils who completed KS4 in mixed schools, 27.0% achieved a grade 6 or above in GCSE physics or double science, compared to more than half (50.1%) of those in single sex schools.

In some cases, a single science GCSE in physics may be an entry requirement – 81.2% of A-Level physics entrants held one in 2021. And again – as we’d expect given their relatively high attainment – girls in single sex schools were far more likely to take triple science GCSE than their peers in mixed schools. 41.6% did so in 2019, compared to 26.4% of those in mixed schools.

On top of the differences in attainment, there are differences in pupil characteristics. Girls in single sex schools are less likely to be disadvantaged than those in mixed schools; 22.5% of girls who completed KS4 in single sex schools in 2019 had been eligible for free school meals at some point in the last six years, compared to 25.6% in mixed schools.  They were also more likely to have English as an additional language (29.3% had EAL vs 14.9% in mixed schools), and over a third (37.8%) were located in London. Finally, they were far more likely to attend a selective school – 27.6% of female pupils in single sex schools did so, compared to just 1.4% of those in mixed schools.

Controlling for the differences

So what is the impact of completing Key Stage 4 in a single sex school on the likelihood of a girl going on to take A-Level physics?

I’ve estimated this by fitting logistic regression models to the data, both with and without controlling for differences in prior attainment and other characteristics.

The first model shows what the estimated impact is if we don’t worry about the differences in prior attainment, triple / double science GCSE and other characteristics. And the second the estimated impact if we do try to account for these differences.[1]

The impact is given in odds ratios, which can be a bit tricky to interpret. However, in this case, given that girls progressing to A-Level physics, is sadly, a fairly rare event, the odds ratios can be said to be roughly the same as the relative likelihood of girls in single sex schools going on to study A-Level physics.[2]

That might still sound a bit tricky to interpret. What I mean is that, if we ignore differences in attainment, likelihood of entering triple science, and other characteristics, the chances of a girl from a single sex school going on to enter A-Level physics are around 3.1 times higher than those of a girl from a mixed school.

But if we were to compare two girls with the same prior attainment and other characteristics, the one from a single sex school would only be around 1.3 times more likely to study A-level physics than the one from a mixed school.

So the differences in prior attainment and other characteristics explain almost all of the differences in progression to A-Level physics.

Summing up

I’ve often wondered if more single sex education might solve some of physics’s woes when it comes to gender balance at A-Level.

But – while it might make some difference – it looks as though most of the difference in progression from girls in single sex schools can be explained by looking at differences in attainment and pupil characteristics.

So the search for the silver bullet goes on.

Notes

[1] The model controlled for: grade in physics / double science GCSE, grade in maths GCSE, whether they took triple science, FSM6, EAL, region, school selectivity.

[2] Odds ratios are the ratio of the odds of two events occurring. In this case, they are the ratio of the odds of a girl from a single sex school entering A-Level physics, and a girl from a mixed school entering A-Level physics. Odds ratios only have the relatively straightforward interpretation described in the text when the events they are describing is rare.

Want to stay up-to-date with the latest research from FFT Education Datalab? Sign up to Datalab’s mailing list to get notifications about new blogposts, or to receive the team’s half-termly newsletter.