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Upload any of these mistakes to Lion City Scholar — AI will identify the exact error pattern and generate targeted practice at your child's level. Try it free →
Common P3 Maths Mistakes and How to Fix Them
Why P3 Maths Gets Harder
P3 is where maths shifts from basic arithmetic to problem solving. Students who breezed through P1-P2 suddenly struggle. Here are the most common mistakes and how to fix them.
1. Multiplication Table Gaps
The mistake: 7 × 8 = 54 (should be 56) Why it happens: Students memorise tables sequentially but cannot recall individual facts quickly. Fix: Practice multiplication facts as random flashcards, not sequential chanting. Target the hard ones: 6×7, 7×8, 8×9, 6×8.2. Regrouping Errors in Subtraction
The mistake: 503 - 247 = 344 (should be 256) Why it happens: Students forget to regroup across zeros. Fix: Practice with numbers containing zeros specifically. Use place value charts to make regrouping visible.3. Confusing "More Than" and "Less Than"
The mistake: "Ali has 15 more stickers than Ben. Ali has 42 stickers. How many does Ben have?" Student answers 57. Why it happens: Students see "more" and automatically add. Fix: Ask your child to draw the problem. Who has more? Draw that bar longer. This builds understanding before calculation.4. Forgetting Units in Answers
The mistake: Writing "12" instead of "12 cm" or "$12" Fix: Train your child to circle the unit in the question BEFORE solving.5. Fraction Misconceptions
The mistake: Thinking 1/3 is bigger than 1/2 (because 3 > 2) Fix: Draw fraction bars side by side. Visual comparison is more powerful than explanation.6. Time Calculation Errors
The mistake: "The show starts at 10:45am and lasts 1 hour 30 minutes. What time does it end?" Student answers 11:75am. Fix: Use a clock. Physically move the hands. Digital calculation of time confuses children.7. Not Reading the Question Fully
The mistake: Finding the total when the question asks "how many more". Fix: Underline the question word (how many MORE / FEWER / LEFT / ALTOGETHER) before solving.8. Skipping the Working
The mistake: Writing only the final answer, which is wrong, with no partial credit. Fix: Insist on writing at least one line of working for every problem. Model method helps here.Upload any of these mistakes to Lion City Scholar — AI will identify the exact error pattern and generate targeted practice at your child's level. Try it free →
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