Every summer, students discover that the mark they needed for a grade 7 or an A was not the mark they were told to aim for. That is not the boards moving the goalposts — it is how the system is designed to work.
A grade boundary is the minimum raw mark needed for a grade on a specific paper, in a specific series. It is set after marking, once the board can see how the cohort performed on that exact paper.
Why boundaries move
Papers are never identically difficult. If a paper turns out harder than intended, the raw mark needed for each grade falls; if it is easier, the boundary rises. The point is that a grade should mean the same thing year to year, even when the paper does not.
- Paper difficulty — the biggest driver of year-on-year movement.
- Cohort performance — statistical predictions based on prior attainment of the entry.
- Senior examiner judgement — scripts around the boundary are reviewed by hand.
- Component weighting — for multi-paper subjects, boundaries are set per component and then combined into an overall subject boundary via a uniform mark scale.
What this means for your revision
Chasing 'the boundary from last year' is a weak target, because that number is a snapshot of one paper. What is stable is the distance between your raw mark and the boundary range across several recent series.
The practical version: mark your practice paper against the official mark scheme, then compare that raw mark to the real published boundaries for that exact paper. If your mark sits above the top boundary of the last three series, that grade is genuinely secure. If it swings across two grades, it is not.
Common misreadings
- Treating UMS or scaled marks as raw marks — they are different scales.
- Comparing boundaries across boards. AQA, Edexcel and OCR set their own, on their own papers.
- Comparing across tiers. Foundation and Higher boundaries are not interchangeable.
- Assuming a percentage. A 'grade 7' is not a fixed 70%; on some papers it has been well below that.