The Most Common Complaint After a Maths Exam
I got the right answer but still lost marks. This happens to more students than you might think, and it is almost always caused by the same problem: the mark scheme does not just check your answer — it checks your method. On any question worth 3 or more marks, the majority of those marks are for method. If there is no written working, the examiner has nothing to award those marks against. The rule is simple but its consequences are not always obvious. On a 4-mark question with a mark scheme of M1, M1dep, A1, A1: a student who writes only the correct final answer can earn at most the final A1. That is 1 out of 4. A student who shows correct method but makes an arithmetic error at the last step can earn M1, M1dep, and potentially the first A1 — that is 3 out of 4. Showing your working on a 4-mark question is worth three times as much as getting the right answer alone.
The Working Marks Breakdown
The distribution of marks across a question tells you immediately how important working is. Here is what typical mark distributions look like at each question value.
- 1-mark questions (B1): These are usually standalone marks for recall, reading a value, or a single-step calculation. One correct answer is sufficient. No extended working needed.
- 2-mark questions (M1, A1): One method mark and one accuracy mark. Write one line of working showing your method, then your answer. Without that line, if your answer is wrong you score 0.
- 3-mark questions (M1, M1dep, A1 or M1, A1, B1): Two steps of method plus a final answer, or method plus answer plus a reason. Show each step separately. The dependent M1 can only be earned if you show the first step.
- 4-mark questions (M1, M1dep, A1, A1): Three marks are for method and process, one is for accuracy. Even a completely wrong final answer can earn 3 out of 4 with clear working.
- 5 to 6 mark questions: Extended multi-step problems where every line of working has potential mark value. Never attempt to shortcut these in your head.
Worked Example 1 — What Counts as Working
Question (2 marks): Solve 3x + 7 = 22. Student A writes only: x = 5. No working. Mark scheme: M1 for rearranging to 3x = 15. A1 for x = 5. If the answer is correct, A1 is awarded. But M1 is not available without evidence of the rearrangement step. If the student had written x = 6 with no working, they score 0. With working (3x = 15), they score M1 and the error on the division costs only the A1. Student B writes: 3x + 7 = 22, so 3x = 15, so x = 5. Mark scheme: M1 for 3x = 15. A1 for x = 5. Result: 2 out of 2. Student C writes: 3x = 15, so x = 6. Arithmetic error on the division. Mark scheme: M1 for 3x = 15 (rearrangement is correct). A0 for x = 6. Result: 1 out of 2 — the method mark is saved. The key insight: writing 3x = 15 is enough for the method mark. You do not need to explain every step in prose. A single line of intermediate algebra is sufficient working for M1.
Worked Example 2 — Non-Calculator Arithmetic
Question (3 marks, Paper 1, non-calculator): Calculate 347 × 24. Show your method. On AQA and Edexcel Paper 1 (non-calculator), method marks are available for arithmetic methods even when the final answer is wrong. This means a student who uses column multiplication and makes one error in the final addition still earns the method marks. Student uses column multiplication correctly, aligns digits properly, but makes an addition error in the final step and writes 8,228 instead of 8,328. Mark scheme: M1 for a correct multiplication method. A1 for correctly completing most of the multiplication working. A1 for 8,328. The student earns 2 out of 3 because the method is clearly shown. Student does it in their head and writes only: 347 × 24 = 8,228. Mark scheme: Only A1 available if the answer is correct; no M1 without visible method. Since 8,228 is wrong, this student earns 0 out of 3. This is a hard lesson, but it is a clear one. On non-calculator questions, showing your arithmetic method is not optional — it is the mechanism by which marks are protected when answers go wrong.
Worked Example 3 — Show That Questions
Question (3 marks): Show that the area of a triangle with base 8 cm and perpendicular height 6 cm is 24 cm². Show that questions are a special case. Because the answer is given in the question, the mark scheme focuses entirely on the quality of working. You must show every step of the reasoning. Student A writes: Area = ½ × base × height = ½ × 8 × 6 = 24 cm². Mark scheme: B1 for stating the correct formula. M1 for substituting base = 8 and height = 6. A1 for reaching 24 cm². Result: 3 out of 3. Student B writes: 0.5 × 8 × 6 = 24. On most mark schemes this earns all 3 marks because the structure of the method is visible — the formula, the substitution, and the calculation are present even if merged into one line. However, on mark schemes that require the formula to be stated separately (such as some AQA Higher questions), Student B might earn only 2 out of 3. Student C writes: 8 × 6 = 48, then 48 ÷ 2 = 24. This is fine — it shows the method in a slightly different order. Mark schemes typically award this as equivalent working. The safe approach: always write the formula as a formula with letters or words, then substitute the numbers, then calculate. This guarantees the method mark is available even if the arithmetic goes wrong.
When You Do NOT Need Extended Working
Not every question needs multiple lines of working. Knowing when minimal working is sufficient saves time and prevents students from over-writing on simple questions.
- 1-mark questions (B1 only): The mark is for the answer alone. Write the answer. Examples include: write down the value of, state the gradient, give a reason why, write down the next term. These do not require method working.
- Write down questions: The phrase write down signals that no extended method is expected. The answer can be read directly from a graph, table, or diagram. A single value is the required response.
- Multiple-choice or matching questions: Circle the answer. No working needed, though a line of working protects against transcription errors.
- Simple 1-step calculations worth 1 mark: If a question asks for 20% of £60 and is worth 1 mark, writing £12 is sufficient. If the same calculation leads into a 4-mark problem, showing the step still protects you.
Practical Habits That Protect Your Working Marks
These habits, applied consistently in every exam, make a measurable difference to your mark total.
- One step per line. Do not cram multiple algebraic steps into one line. Each line of working gives the examiner another opportunity to award a mark.
- Write the formula first. For any formula-based question — trigonometry, area, Pythagoras, quadratic formula, percentages — write the formula with letters before you substitute numbers. This earns the formula mark separately from the substitution mark.
- Use the space provided as a signal. If a question has 8 lines of working space, the examiner expects roughly 8 lines of working. If you have written 2 lines, you have almost certainly skipped a step that carries a mark.
- Never erase — cross out instead. If you make an error, put a single diagonal line through it. The original working remains readable and may still earn marks. Completely erased working cannot earn any marks.
- Label your answers clearly. Write the answer at the end of your working with a box around it or on its own line. This makes it easy for the examiner to locate your final answer and award the accuracy mark.