If you tutor across more than one exam board — and most A-level and IGCSE maths tutors do — you will have noticed that a "correct" answer is not always marked the same way. The mathematics is universal; the mark schemes are not. Each board has its own conventions for awarding method, accuracy and independent marks, and knowing those differences is part of marking your students the way their examiner will.
This is a practical comparison of how Edexcel, CIE (Cambridge) and AQA approach maths marking, and what it means when you sit down with a stack of scripts.
Before the differences, the common ground. All three boards mark on the same underlying philosophy: credit is given for evidence of correct mathematics, not just the final answer.
If you understand that framework, you can mark any of the three boards competently. The differences are in the detail — and the detail is where marks are won and lost.
Edexcel mark schemes are known for being highly structured and explicit. They tend to spell out the acceptable method in detail, list alternative valid approaches, and state precisely what constitutes the accuracy mark. For tutors, this is a gift: there is usually little ambiguity about why a mark is awarded.
The trade-off is volume. Edexcel schemes can be dense, and applying them faithfully means reading carefully through the awarding notes for each part — particularly around what counts as an acceptable alternative method.
CIE mark schemes, used widely in international schools, lean on a recognisable set of marking abbreviations — you will see oe ("or equivalent"), soi ("seen or implied") and cao ("correct answer only") throughout. The "or equivalent" and "seen or implied" conventions matter enormously: CIE often credits a step the student clearly used even if they did not write it out in full, which rewards mathematical intent.
For tutors, the lesson is to read CIE schemes generously where the abbreviations invite it, and strictly where "cao" demands an exact answer. Marking CIE as if it were Edexcel — or vice versa — is a common source of inconsistency.
AQA mark schemes are clear and approachable, with a strong emphasis on method and on accepting a range of valid student approaches. AQA is often explicit about follow-through and about not double-penalising, and its notes are written to help a marker reach a fair decision quickly. Tutors generally find AQA schemes the most readable of the three.
The watch-point is the same as ever: do not assume an AQA convention carries over to another board's paper.
The practical takeaway is that switching boards mid-pile is where errors creep in. You internalise one board's conventions, then carry them across to another board's script without noticing. The result is inconsistent marks and feedback that does not quite match what the examiner would say.
Three habits help:
This is also where a board-aware tool earns its place. MarkMate marks each handwritten answer against the specific board's official mark scheme — Edexcel, CIE or AQA — applying that board's own conventions for method, accuracy and independent marks, pinpointing the step that went wrong, and writing feedback your student can read. It removes the risk of accidentally marking a CIE script with an Edexcel head on, and gives you a consistent draft in seconds.
The boards agree on the philosophy and differ in the detail. Edexcel is explicit and structured, CIE rewards implied and equivalent working through its abbreviations, and AQA is readable and follow-through friendly. Mark to the board in front of you, keep its scheme to hand, and your students get marks and feedback that match the real exam.
Tutoring across Edexcel, CIE and AQA? Mark every script against the right board's scheme.
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