Answer? Law and astronomy, although there are very few entries each year. The much bigger issue is that GCSEs in modern foreign languages are graded more severely than other subjects.

Just before Christmas, Ofqual published a set of very interesting working papers about inter-subject comparability and subject difficulty in GCSEs and A levels. The conclusion is unequivocal. Grades in some subjects are higher (or lower) than in others.

In this blog, we look at the difficulty of different subjects at GCSE as we’ve written about A levels previously. As some astute readers noted in response to that blog, strictly speaking what we are actually discussing is severity of grading rather than subject difficulty. Some subjects are graded more (or less) severely than others.

Let’s begin by grabbing some data. We use results in full course GCSEs entered by all pupils who reached the end of Key Stage 4 nationally in 2015 in all institutions including independent schools, special schools and alternative provision. A pupil’s first entry is used in cases where a subject has been entered more than once.

### Assigning grades on the basis of latent ability

Underlying our analysis is a statistical model that assumes that grades in GCSEs are awarded on the basis of both the ability of pupils and the difficulty of each subject. As we wish to compare different subjects, we assume that the measure of ability does not vary between subjects but the level of difficulty does.

A measure of each pupil’s latent ability is estimated from the data. This scale can then be sliced up into grades. Chart 1 shows the cut-points of our notional ability scale for a subject of average difficulty. This suggests, as we have discussed previously, that intervals between grades are not equal. In other words, the difference between G and F is not the same as the difference between B and A.

Chart 1: GCSE grade cut-points on the latent ability scale

### Variation in difficulty between subjects

Table 1 below presents all subjects with at least two thousand entrants amongst the 2015 national KS4 cohort in ascending order of difficulty (or grade severity, if you prefer).

Pupils entered for Polish, Chinese, Arabic, Italian, Urdu and art & design tend to achieve better grades in those subjects than might be expected from their latent ability. This makes sense: these subjects tend to be entered by pupils who are either native speakers or who have an aptitude for art & design. In other words, they tend to be more self-selecting than in other subjects and so it is little surprise that results tend to be higher. I very much doubt that Polish would remain the least severely graded subject if large numbers of pupils who were not Polish started to enter it.

By contrast, entries in law, astronomy, applied engineering, general studies and German tend to be more severely graded. Perhaps more worrying is the difficulty associated with the three most common modern foreign languages taught in schools: French, German and Spanish.
The scale on which subjects are ranked in Table 1 is not particularly meaningful so Chart 2 shows what it means in practice for a selection of subjects. Here we show the difference in percentages of A*-C and A*-A grades awarded compared to a subject of average difficulty.

Chart 2: Differences in percentages of A*-C and A*-A grades awarded compared to a subject of average difficulty

### So what?

For a start, Ofqual deserves credit for launching this debate. But then we have to ask whether we should have consistency of grading between subjects. Is it even technically feasible? If we cannot have a perfect balance between subjects is there anything we could do to get a bit closer?

Even if we “fix” the current inconsistency between subjects, there is no guarantee that grades won’t diverge again in the future. Perhaps French used to be no more severely graded than maths. The difference we see today may be the product of changes in teaching and attitudes.

Or should we just live with inconsistency? If so, we have to understand the consequences. Schools’ curriculum choices influence their performance measures. At present the more that schools offer MFL the more they are effectively being penalised.

Table 1: Estimated GCSE subject difficulty, pupils reaching the end of KS4 in 2015

 Subject Change in log-odds of higher grade compared to maths Entries Polish 5.24 3768 Chinese 2.49 3153 Art & Design (Photography) 1.51 22006 Arabic 1.50 3035 Italian 1.45 3854 Urdu 1.21 4087 Art & Design (Textiles) 0.84 6749 Art & Design (Fine Art) 0.64 50999 Art & Design 0.62 86018 Expressive Arts & Performance Studies 0.48 3151 D&T Textiles Technology 0.47 24108 Art & Design (Graphics) 0.45 6874 D&T Food Technology 0.30 38263 Film Studies 0.30 6209 Media/Film/TV Studies 0.26 51402 Home Economics: Child Development 0.26 18136 Performing Arts 0.21 5937 Religious Studies 0.11 267864 English Literature 0.06 405670 Drama & Theatre Studies 0.06 70655 English Language & Literature 0.06 64535 Mathematics 0.00 542020 Physical Education/Sports Studies 0.01 110391 Social Science: Citizenship -0.02 20731 Information & Communications Technology -0.02 99150 English Language -0.07 298688 Physics -0.12 122528 Health & Social Care -0.12 7079 Chemistry -0.13 123333 Latin -0.13 8337 D&T Resistant Materials -0.14 50826 Dance -0.15 11953 Biology -0.17 126042 Home Economics: Food -0.22 8628 Methods in Mathematics -0.34 12198 Office Technology -0.41 13340 Applications of Mathematics -0.43 12097 Sociology -0.43 21274 D&T Electronic Products -0.44 7862 Science (Core) -0.45 366238 D&T Product Design -0.48 37750 Music -0.49 43502 Additional Science -0.53 326679 Statistics -0.57 51647 Geography -0.57 210919 History -0.63 228569 Business Studies -0.72 73819 D&T Graphic Products -0.73 31708 D&T Systems & Control -0.85 2969 Spanish -0.99 84846 Classical Civilisation -1.10 3971 Psychology -1.21 15897 Computer Studies/Computing -1.28 33378 Economics -1.29 9414 French -1.34 150702 Humanities: Single -1.35 8326 German -1.44 52621 General Studies -1.71 9302 Applied Engineering -1.88 6257 Astronomy -2.46 2300 Law -2.47 2196