OCR A-Level Maths revision guide: A vs MEI, papers and the plan
OCR offers two A-Level Maths courses. OCR A (H240) has three 100-mark, two-hour papers: Paper 1 is pure, Paper 2 is pure plus statistics, Paper 3 is pure plus mechanics. OCR MEI (H640) has three 120-mark papers mixing pure with applied, and its Paper 3 includes a comprehension section built around an unseen mathematical article. The revision method is the same — questions early, marked honestly — but MEI students must additionally practise reading and answering questions about a piece of mathematical writing.
The first thing to know about OCR maths is that there are two of it. Your school teaches either OCR A or OCR MEI, and the revision advice diverges — so check your exam entry before anything else on this page.
The two OCR specifications
| Paper | OCR A (H240) | OCR MEI (H640) |
|---|---|---|
| Paper 1 | Pure, 2h, 100 marks | Pure + Mechanics, 2h, 120 marks |
| Paper 2 | Pure + Statistics, 2h, 100 marks | Pure + Statistics, 2h, 120 marks |
| Paper 3 | Pure + Mechanics, 2h, 100 marks | Pure + Comprehension, 2h, 120 marks |
OCR A mirrors the national pattern — pure dominates and the applied strands sit in their own papers. MEI spreads everything differently: each paper is 120 marks, mechanics and statistics are embedded with pure from Paper 1, and Paper 3 reserves a section for the comprehension, where you answer questions on a mathematical article inserted into the paper.
The MEI comprehension — what it actually is
Paper 3 of MEI includes an insert: a short piece of mathematical writing — a proof, a modelling argument, an application — that you have not seen before. The questions ask you to follow the argument, fill in steps, correct errors and extend it. Students who revise only by drilling techniques find it disorienting. The fix is simple and cheap: practise the last section of recent MEI Paper 3s until following someone else's reasoning feels normal.
What OCR asks that trips people up
- "In this question you must show detailed reasoning" — a printed instruction meaning calculator answers alone score almost nothing.
- Command-word precision: OCR uses "determine", "verify" and "show that" with distinct meanings, and the mark scheme holds you to them.
- Synoptic leaps — OCR happily puts a Year 1 method inside a Year 2 question with no warning.
- On MEI Paper 3, losing marks on comprehension parts that required nothing more than careful reading.
- Statistics questions that ask you to criticise a sampling method or a model — worth a mark or two, skipped by most.
Worked questions in the OCR style
Show that the equation x³ − 3x − 5 = 0 has a root between 2 and 3, and use the iteration xₙ₊₁ = ∛(3xₙ + 5) with x₀ = 2 to find it to 2 decimal places.
- Change of sign: f(2) = 8 − 6 − 5 = −3 and f(3) = 27 − 9 − 5 = 13. The sign change on a continuous function means a root lies between 2 and 3 — write both evaluations down; OCR wants the detail.
- Iterate: x₁ = ∛(11) ≈ 2.224, x₂ = ∛(11.67) ≈ 2.267, x₃ ≈ 2.277, x₄ ≈ 2.279.
- The values converge to 2.28 (2 dp). Verify by checking f(2.275) and f(2.285) change sign if the question asks for proof of accuracy.
Root ≈ 2.28. 'Detailed reasoning' means every evaluated step is written — a bare calculator answer scores one mark at best.
The article states that for small θ, sin θ ≈ θ. Using this approximation, show that for small oscillations a pendulum's equation becomes linear.
- The pendulum equation is θ'' = −(g/L) sin θ — the sin θ is what makes it non-linear.
- For small θ, replace sin θ with θ: θ'' ≈ −(g/L)θ.
- This is now linear — of the form x'' = −ω²x, simple harmonic motion with ω² = g/L.
- Comprehension questions reward you for using the article's notation — mirror it in your answer.
θ'' ≈ −(g/L)θ — linear SHM. The marks are for the substitution and the recognition, not for solving anything.
Common OCR mistakes
- Relying on the calculator's solve function on a 'detailed reasoning' question — the working is the assessed skill.
- Not knowing which of the two specifications you are actually sitting.
- MEI students treating the comprehension as unreadable — it is usually the most predictable section of Paper 3.
- Rounding before the final line, especially in iteration and normal-distribution questions.
- Skipping the 'state an assumption' line in mechanics — it is a free mark for a phrase like 'modelled as a particle'.
Your OCR revision checklist
- I know whether I am entered for H240 or H640, and I have the right past papers.
- I write full algebraic working on every 'detailed reasoning' question.
- I have done at least five timed papers per paper code.
- MEI: I have practised three or more comprehension sections and can follow an unfamiliar argument.
- I can criticise a sampling method and state a modelling assumption from memory.
- I have read the OCR examiner reports for my two weakest papers.
OCR's 'detailed reasoning' instruction is really asking one thing: can you show the maths, not just produce the answer? If your working keeps losing marks, put your attempt in front of Lumi and let it mark the gaps line by line — that is the feedback loop past papers alone cannot give you.
What to take from this
- Check whether your school teaches OCR A (H240) or MEI (H640) — they are different specifications with different papers.
- On OCR A, pure appears in every paper; statistics lives in Paper 2 and mechanics in Paper 3.
- MEI's comprehension paper is unique in England — it rewards students who can read maths, not just do it.
- OCR mark schemes reward method heavily; a partially correct attempt still scores.
- Both courses are three two-hour papers, all calculator, all at the end of Year 13.
Questions people also ask
OCR A (H240) separates pure into Paper 1 and applied into Papers 2 and 3. MEI (H640) mixes pure with applied across all three 120-mark papers and adds a comprehension section to Paper 3, where you answer questions on an unseen mathematical article.
It is different rather than harder — it tests whether you can follow a written mathematical argument and spot or fix errors in it. Students who practise it find it predictable; students who only drill techniques find it strange. A few past attempts remove the strangeness.
You can use it for arithmetic, but the assessed skill is the algebraic method. A correct answer from a solver with no written method scores little. Write every line as though the calculator were not there.
On OCR's website under Mathematics H240 and H640 — question papers, mark schemes and examiner reports are all free. The examiner reports are unusually honest about where marks are lost.