After a mixed practice set, the question order is the least useful way to read your results. A better method is to name the skill that failed in each wrong answer and count them. This lesson belongs to mixed original practice.
How do I build an error log?
Make a table with four columns: question, what went wrong, skill category, fix. Keep the “what went wrong” note short and honest.
Useful categories for Combined Science 0653:
- Recall: you did not know the fact.
- Units: the value was right, the unit missing or wrong.
- Graph or table reading: a value or trend was misread.
- Command word: you answered a different question from the one asked.
- Applying a model: you knew the idea but chose the wrong one.
- Arithmetic: a slip in the calculation.
Worked example
All numbers are invented for practice. A student loses marks on ten questions in a mixed set.
| Q | Subject | What went wrong | Skill |
|---|---|---|---|
| 2 | Physics | Wrote 7.5 with no unit | Units |
| 4 | Biology | Read 36 °C as 38 °C on the graph | Graph reading |
| 5 | Chemistry | Described the reaction instead of explaining | Command word |
| 7 | Physics | Forgot the unit again | Units |
| 8 | Chemistry | Misread the scale on the axis | Graph reading |
| 9 | Biology | Did not recall enzyme name | Recall |
| 11 | Physics | Read the wrong row in the table | Graph reading |
| 12 | Biology | Used diffusion for an osmosis question | Applying a model |
| 14 | Chemistry | Read a peak value wrongly | Graph reading |
| 15 | Physics | Left out the unit | Units |
Count by skill: graph reading 4, units 3, command word 1, recall 1, applying a model 1. Total 4 + 3 + 1 + 1 + 1 = 10, which matches the ten questions.
Percentage: graph reading is 4 ÷ 10 = 40% of the lost questions, and units is 3 ÷ 10 = 30%.
By paper order, this looks like errors in all three sciences. By skill, 70% of the loss comes from two habits, and neither needs new content. The next session should be short drills on reading scales and checking units.
The mistake to watch for
A common slip is to write “careless mistake” as the reason.
Mistaken log entry: “Q7: careless.”
This cannot be fixed, because it does not say what to do differently.
A usable entry says what happened: “Forgot the unit after substituting.” The fix then follows: “Write the unit on every line of working.”
Check yourself
1. A student has twelve lost questions: 5 graph reading, 3 units and 4 recall. What percentage is graph reading, to the nearest whole number?
Show answer
5 ÷ 12 = 0.4167, so 42% to the nearest whole number. Check: 5 + 3 + 4 = 12.
2. Another student has eight lost questions: 2 units, 4 command word, 2 recall. Which skill should the next session focus on, and what share is it?
Show answer
Command words, with 4 ÷ 8 = 50% of the lost questions.
3. Rewrite “Q3: silly” as a useful log entry for a graph question where the axis scale was misread.
Show answer
“Q3: misread the scale, each square was 2 not 1. Fix: write the value of one square before reading any point.”
Where this leads next
The log feeds directly into building a balanced repeat session. The mixed practice set gives you material to log, and the scientific investigation critic can help when your errors cluster around experiment questions.
If you want a second pair of eyes on your pattern, that is a natural job for online one-to-one Combined Science tuition.