Making sense of missing KS2 data
As you know, 2025 is the first of two years where Year 11 students won’t have KS2 scaled scores due to the Covid-19 pandemic. Normally, the Sisra Analytics team at Juniper Education produces analysis after the DfE releases their Attainment 8 estimates, comparing them to our collaboration data to show how closely they align. While we can’t do this for the next couple of years, we were keen to find another way to use the data we’ve collected to provide schools with valuable insights.
Barnaby Grimble at our partners, Pupil Progress, recently published an article about grade boundaries, and how they change each year to balance the results achieved by students. This means that even though grade boundaries change, the overall distribution of grades should not change much from year to year. You can find the original article here.
How grade boundary shifts impact final results
I thought it would be helpful to test this hypothesis against the figures we collect through our data collaboration.
To start, I examined the overall grade boundary changes and grade distributions. Below is the information from Barnaby’s article, showing the overall grade boundary shifts across all exam boards and subject areas from 2024 to 2025:
And here are the grade percentages from our collaboration data, also for the last two years
As you can see, the 1% average increase in grade boundaries across most exam boards didn’t lead to the same level of change in final grades. In fact, when we average out the small shifts across all grades, we see a 0% overall change — meaning outcomes have remained broadly the same. What this grade boundary shift tells us is that, on average, students performed slightly better across their subjects compared to 2024. The grade boundaries were adjusted to balance this out, ensuring attainment stays consistent year on year.
This process is normal and happens every year. There can be many reasons why students perform slightly better from one year to the next, as Barnaby explains in his article:
The exam paper differences mentioned here are part of the reason the grade boundary changes are different for the individual exam boards.
Breaking down 2025 grade boundary shifts by subject
When it comes to subject analysis, subjects with smaller entry cohorts will generally see larger grade shifts year-on-year, as each individual student’s outcomes have a larger impact on the grade averages. Taking a large entry subject like maths, we can see some marked shifts in the grade boundaries:
Again though, this is not matched by large changes in grade distribution, which also average out at zero across all grades:
In combined science we see the same picture, relatively large percentage swings in the grade boundaries, with static outcomes over the last two years, averaging out to zero:
Why is this important?
Combining the information for the grade distributions with the small changes in grade boundaries, gives confidence in Pupil Progress' advice on what grade boundaries to use for your grade predictions for the 2026 exam series. The relatively small changes in numbers of students achieving each grade means that, as long as papers have a very similar level of challenge and no specification changes, then it is sensible to use the 2025 grade boundaries plus 3-4% in your assessment tracking as suggested by Pupil Progress in their article.
Using Pupil Progress to track your assessments and calculate accurate grades in the same way as the exam boards do will support your quality of data analyses at a school or trust level using Sisra Analytics. This in turn will give you confidence in the strategic decisions you make as a leadership team to raise attainment of your students.
If you’d like to dig into this further, you can find percentage grade boundary shift information for all subjects here.
You can also find out more about our partnership with Pupil Progress and how, alongside Sisra Analytics, it can help you track and analyse subject performance more effectively.
