GCSE exam technique for maths
Maths · GCSE · The School
Command words decide the work
"Work out" wants the answer with working. "Show that" wants you to reach a GIVEN result — start from the other end and meet it. "Prove" needs a general argument, not one example. "Give a reason" needs a sentence. The mark allocation tells you the depth: 1 mark is a line, 4 marks is four visible steps.
Method marks are most of the paper
A wrong final answer with correct working usually scores most of the marks; a correct answer with no working can score one. So write every stage, keep it in order, and never rub out a wrong attempt — cross it through with one line, because uncrossed work is marked and might be the version that earns marks.
The last thirty seconds
Before moving on: does the answer have units? Is it a sensible size (an estimate check)? Did you answer what was asked — the perimeter, not the area; x, not the angle? Have you rounded as instructed (2 d.p., 3 s.f.)? These four checks recover more marks per minute than any revision technique.
"A rectangle is 7 cm by 4 cm. Work out its perimeter. (3 marks)" ANSWER A: "22 cm" — correct, one mark, because there is no method to credit. ANSWER B: "7 + 4 = 11; 11 × 2 = 22; perimeter = 22 cm" — three marks. Now suppose the arithmetic slipped and you wrote 21 cm. Answer A scores zero. Answer B still scores two, because both method steps are visible. Same knowledge, three marks apart.