Past papers are the closest thing to the real exam, which makes them the most informative resource you have — and the easiest to waste. Used casually they measure nothing; used properly each one produces a short list of exactly what to fix.
The routine
- Sit the paper timed, in one go, with only the formula booklet and your own calculator.
- Mark it against the official mark scheme, awarding marks exactly as written.
- For each lost mark write one word: recall, method, selection, or arithmetic.
- Group those words. The largest group is your next week of revision.
- Redo the failed questions cold a week later.
How many papers
Roughly one paper a fortnight through the spring term, rising to one a week in the final month, is enough for most students — provided each is analysed. Ten analysed papers beat thirty unanalysed ones, and running out of unseen papers in April is a real cost.
Open-book practice has its place
Early in a topic, working through questions with notes available is useful learning. It is just not assessment. Keep the two activities separate so you always know which one you are doing.