(And How to Avoid Them)
After reviewing hundreds of matric papers and working closely with Grade 10-12 students, we've identified the mistakes that cost learners the most marks. The good news? They're all avoidable.
Many students try to do calculations in their heads to finish faster. This leads to silly errors and, ironically, costs more time when you have to redo the question.
✓ The Fix:
Write out every step. Markers award method marks, so even if your final answer is wrong, you'll still earn points. Plus, it's easier to spot your own errors.
Answering a different question than what was asked. Common examples: finding x when they asked for y, or giving coordinates when they wanted the equation.
✓ The Fix:
Underline or highlight exactly what the question is asking for. Before moving on, check: "Did I actually answer what they asked?"
Losing track of negative signs, especially when multiplying or dividing. One wrong sign can make your entire answer incorrect.
✓ The Fix:
Circle or box negative signs as you write them. When multiplying/dividing, write out the sign rule: (−) × (−) = (+) next to your working if needed.
Doing trigonometry with your calculator in radians instead of degrees (or vice versa). This gives completely wrong answers.
✓ The Fix:
Before every exam, check your calculator is in DEG mode (for CAPS). Write "DEG ✓" at the top of your answer sheet as a reminder that you checked.
In functions and equations, forgetting to mention restrictions like x ≠ 0 or the domain. Easy marks left on the table.
✓ The Fix:
Whenever you see a fraction or square root, immediately ask yourself: "What values would make this undefined?" Write restrictions as you go, not at the end.
Spending 20 minutes on a 3-mark question, then rushing through the 10-mark questions at the end.
✓ The Fix:
Use the rule: 1 mark ≈ 1 minute. If a question is worth 4 marks, spend roughly 4 minutes on it. If you're stuck, mark it and move on — come back later.
Getting an answer like "the person is -5 years old" or "the length is 150km" for a classroom problem — and not questioning it.
✓ The Fix:
Always ask: "Does this answer make sense in real life?" If it's a word problem, substitute your answer back into the original context to verify.
Rounding intermediate answers, then using those rounded numbers for further calculations. This compounds errors and gives a wrong final answer.
✓ The Fix:
Keep full calculator values until the very end. Use the ANS button to carry forward exact values. Only round your final answer (usually to 2 decimal places unless specified).
Seeing a hard question and skipping it entirely. Zero attempt = zero marks, guaranteed.
✓ The Fix:
Always write something. Draw a diagram. Write down the formula. Identify what you know. Partial marks exist — and 2 marks for an attempt beats 0 marks every time.
Trying to remember formulas from memory when there's a formula sheet provided. Or worse, not knowing what's on it.
✓ The Fix:
Study your formula sheet until you know exactly where each formula is. In the exam, glance at it before each section. It's there to help you — use it!
This guide is just the start. If you want personalised tutoring that targets your specific weak areas, we're here for you.
projectodysseus.live | [email protected]