Reading a correction is not the same as learning from it. A proper review finds the cause, turns it into a rule, and tests the rule on a new question.
This resource is part of the student study resources. The mistake log and paper error review can keep the record for you.
What are the five steps?
- Cause. Decide which cause applies: did not know, knew but slipped, misread, or ran out of time.
- Rule. Write one sentence in your own words that would have prevented it.
- Redo. Close the answer and solve the same question again.
- Vary. Change a number or a detail and solve again.
- Log. Write the cause and rule in one line with the date.
What does the review look like on an example?
Here is an original Chemistry question: “Calculate the number of moles in 4.0 g of sodium hydroxide, NaOH. (Na = 23, O = 16, H = 1)”
Your answer is 4.0 ÷ 23 = 0.17 mol. The correct working is molar mass of NaOH = 23 + 16 + 1 = 40 g/mol, so moles = 4.0 ÷ 40 = 0.10 mol.
- Cause: knew the formula, but used the atomic mass of one element instead of the whole compound.
- Rule: “Add up every atom in the formula before dividing.”
- Vary: 9.8 g of H₂SO₄ (H = 1, S = 32, O = 16): molar mass = 2 + 32 + 64 = 98, so 9.8 ÷ 98 = 0.10 mol.
Why is the cause step so important?
Without it, you may revise the whole mole chapter when the real fault was one line. With it, you fix that line and save an evening.
| Cause | Fix |
|---|---|
| Did not know | Learn the idea, then redo |
| Knew but slipped | Add a checking step, such as unit or sign check |
| Misread | Underline the command word and the numbers |
| Ran out of time | Practise timed, skip and return |
How do I spot repeating errors?
After a week, read your log. If “added only one atom’s mass” appears three times, that is your next practice target. I keep making the same mistakes in practice explains this in more depth.
Pair this with practising without peeking at the answer, which covers the attempt before the review.
Try a self-check
Take a marked paper and choose one wrong answer. Write its cause and rule in two lines, then vary it. If you cannot write the rule, the question is a gap, and a teacher can help you through it.
A one-hour trial class (from RM50) is a chance to bring three wrong answers and sort them into the four causes with a teacher.