Exam strategy · Error log · Revision method
How to Build an Error Log and Review Wrong MCQs So You Never Repeat Them
Every wrong answer in practice is a free lesson — but only if you capture it and come back to it. An error log (also called a mistakes book) is the simplest tool that separates steady improvers from those whose scores stay flat. This guide shows exactly what to record, how to review it and how long it takes.
Why most people forget their mistakes
When you check a wrong answer and read the explanation, it feels learned. But memory research consistently shows that most new information fades within days unless it is revisited. That is why the same mistake — confusing the Treaty of Lahore with the Treaty of Amritsar, or dividing instead of multiplying in a percentage question — appears again three mocks later. An error log fixes this by making you revisit each mistake at the right moments.
What to record for each mistake
Keep it short. Long notes are never re-read. Use one line or one card per mistake with five fields:
| Field | Example |
|---|---|
| Topic tag | Punjab history — Anglo-Sikh wars |
| The question (short form) | Battle not part of First Anglo-Sikh War? |
| Your answer and the correct answer | Chose Aliwal; correct: Chillianwala |
| Why you got it wrong (category) | Knowledge gap — mixed the two wars |
| The rule or fact to remember | First war: Mudki, Ferozeshah, Aliwal, Sobraon; second: Ramnagar, Chillianwala, Gujrat |
The last field is the most important. Write it as a rule you could teach someone else.
Tag every mistake by type
Use the same categories you use in mock analysis:
- K — knowledge: you did not know the fact.
- C — concept: you did not know or apply the method.
- S — silly: calculation slip or wrong option clicked.
- R — reading: you misread the question (missed NOT, EXCEPT, "incorrect").
- T — time: you rushed or did not reach the question.
At the end of each week, count the tags. Ten K-tags in Punjab GK tells you to revise that subject; ten S-tags in maths tells you to slow down and check the last step.
The 1–3–7–21 review schedule
Review each mistake at expanding intervals:
| Review | When | What to do |
|---|---|---|
| 1st | Next day | Cover the answer and re-solve or recall it |
| 2nd | Day 3 | Re-solve; if right, mark ✓ |
| 3rd | Day 7 | Re-solve; if right, mark ✓✓ |
| 4th | Day 21 | Final check; if right, move it to the "mastered" pile |
If you get it wrong at any stage, restart the schedule for that item. This is a simple form of spaced repetition, and it is far more effective than re-reading whole chapters.
Making the schedule manageable
- Write the next review date next to each entry, or keep four piles of cards labelled by review stage.
- Spend 15–20 minutes a day on reviews. That is usually enough for 30–50 items.
- On the day before a mock, review only items tagged K and C from the relevant subjects.
Paper notebook or phone?
Both work; what matters is that you use it every day.
- Paper notebook: easy to carry, good for maths working and Gurmukhi. Use a separate section per subject.
- Index cards: ideal for the 1–3–7–21 system because you can sort them into piles.
- Spreadsheet or notes app: easy to filter by tag and date, and good if you study during commutes.
Turning mistakes into practice
An error log also tells you what to practise:
- Find patterns. If five of your last twenty maths errors are from successive percentage changes, that is your next topic-practice session.
- Create variations. Change the numbers in a maths question you got wrong and solve it again. Change one fact in a GK question and ask yourself what would change.
- Teach it. Explaining a mistake to a friend or writing it as a short rule cements it.
- Merge into short notes. Once a mistake is mastered, add the rule to your one-page subject summary for final revision.
Example entries
| Tag | Rule to remember |
|---|---|
| K — Polity | Fundamental Duties: Article 51A; 42nd Amendment 1976; 11 duties now (86th Amendment added the eleventh). |
| C — Quant | Successive changes of +20% and −20% give a net −4% (1.2 × 0.8 = 0.96). |
| R — Reasoning | In "Which is NOT…" questions, check each option against the statement, not against general knowledge. |
| S — Quant | Convert km/h to m/s by multiplying by 5/18, not 18/5. |
| K — Punjabi | ਪੜਨਾਂਵ = pronoun; ਵਿਸ਼ੇਸ਼ਣ = adjective. |
How long before you see results?
Most candidates notice fewer repeated mistakes within two to three weeks of keeping an error log seriously. Over two months, silly and reading mistakes typically fall sharply, because the act of tagging them makes you more careful.
Key points to remember
- Record every mistake in five fields: topic, short question, your answer vs correct answer, reason, and the rule to remember.
- Tag mistakes K, C, S, R, T (knowledge, concept, silly, reading, time).
- Review on days 1, 3, 7 and 21; restart the cycle if you get an item wrong.
- 15–20 minutes a day is enough for 30–50 reviews.
- Count tags weekly to decide what to practise next.
- Record lucky guesses too.
Practice questions
Q1. A price rises by 20% and then falls by 20%. The net change is:
- (a) No change
- (b) 4% decrease
- (c) 4% increase
- (d) 2% decrease
Show answer
Answer: (b) 4% decrease — 1.20 × 0.80 = 0.96, i.e. a 4% decrease.
Q2. To convert a speed from km/h to m/s, multiply by:
- (a) 18/5
- (b) 5/18
- (c) 1000/60
- (d) 60/1000
Show answer
Answer: (b) 5/18 — 1 km/h = 1000 m ÷ 3600 s = 5/18 m/s.
Q3. In a 1–3–7–21 review schedule, when is the third review done?
- (a) Day 3
- (b) Day 7
- (c) Day 14
- (d) Day 21
Show answer
Answer: (b) Day 7 — The reviews are on day 1, day 3, day 7 and day 21.
Q4. You get the same question type wrong because you misread "EXCEPT" each time. Which tag fits?
- (a) Knowledge
- (b) Concept
- (c) Reading
- (d) Time
Show answer
Answer: (c) Reading — It is a reading error; underline key words such as NOT and EXCEPT.
Q5. A candidate reviews 40 error-log items a day at 30 seconds each. How long does the review take?
- (a) 12 minutes
- (b) 15 minutes
- (c) 20 minutes
- (d) 30 minutes
Show answer
Answer: (c) 20 minutes — 40 × 30 s = 1,200 s = 20 minutes.
Frequently asked questions
Should I record questions I guessed correctly?
Yes. A lucky guess hides a knowledge gap. Mark it with a separate symbol and review it like a mistake.
How many entries should an error log have?
There is no fixed number. In an active preparation period, 10–30 new entries a week is common. If you have hundreds of unreviewed items, cut down by keeping only K and C items.
Is an error log useful for current affairs?
Very. Record facts you got wrong in quizzes and review them on the same schedule; current-affairs facts are easy to forget.
Official sources
Rules, dates and figures can change. Always check the latest official notification or government release before relying on a detail.