IGCSE exams don’t just test what students know. They test how well students apply knowledge under time pressure, interpret questions accurately, and present answers in the way examiners award marks. Many students walk out of an exam feeling they “knew the content” yet lose marks on avoidable errors: misreading command words, skipping steps, poor time control, or writing too much in the wrong places.

This blog covers the most common IGCSE exam mistakes across subjects and practical ways to avoid them, especially in Maths, Sciences, English, and IGCSE Physics 0625.

1) Misreading the question (and answering something else)

This is one of the biggest mark-killers across every subject. It happens when students rush, assume they know the question type, and start writing before fully reading.

Common signs

• solving the right topic but the wrong part
• answering with a description when the question asks for an explanation
• giving a final value when the question asks for a method or working
• missing words like “give a reason”, “state”, “calculate”, “compare”

How to avoid it

• underline what is being asked before writing
• circle key terms: describe, explain, calculate, estimate, compare
• write a one-line plan for long questions
• check the number of marks to judge answer length

2) Ignoring command words

Command words decide what kind of answer earns marks. Many students lose marks because the response doesn’t match the required depth.

What examiners look for

• State: short fact, no working, no story
• Describe: what happens, what you see
• Explain: why it happens, linked reasoning
• Compare: similarities and differences
• Evaluate/Discuss: balanced points + judgement

How to avoid it
Create a command-word sheet for each subject and revise it weekly. During past paper practice, label the command word next to the question, then mark your answer based on whether it matched.

3) Poor time management

Students often spend too long on a tough question early, then rush or leave marks later that they could have secured easily.

How it shows up

• unanswered questions at the end
• rushed handwriting and unclear working
• missed easy marks in later sections

How to avoid it

• use mark-based timing (roughly 1 mark ≈ 1 minute is a helpful starting point)
• move on when stuck and return later
• aim to finish 5–10 minutes early for checking
• practise full papers timed, not only topic questions

If you’re using IGCSE online tutoring or igcse online coaching, time strategy should be part of sessions, not an afterthought. Strong online igcse tuition includes timed drills and marking for speed.

4) Not showing working (especially in Maths and Sciences)

Many students lose method marks because they write only the final answer, or their steps are too messy to follow.

Where it hurts most

• algebra and equations
• Physics calculations (substitution, rearranging)
• Chemistry moles and quantitative questions
• graphs and data-based questions

How to avoid it

• write each step on a new line
• show substitutions clearly before calculating
• include units at every stage in Physics
• box the final answer, but keep working visible

This matters a lot in IGCSE Physics 0625, where method marks are often available even if the final number is wrong.

5) Careless arithmetic and algebra slips

These mistakes are common because students focus on the method and assume the calculations will follow.

Frequent culprits

• sign errors when expanding brackets
• dividing incorrectly when rearranging equations
• copying numbers wrongly from the question
• premature rounding
• calculator bracket mistakes

How to avoid it

• estimate before calculating (your answer should “look right”)
• keep fractions and exact values until the final step
• check signs when moving terms across the equals sign
• re-check any answer that looks too big or too small

A-grade students are not perfect. They just catch errors more often before the examiner does.

6) Writing too much (and missing the point)

This is common in English, Humanities, and even Science explanations. Students think longer answers score higher, but examiners award marks for relevance and structure.

How it shows up

• long paragraphs with repeated ideas
• drifting into storytelling rather than answering the question
• no clear point-by-point structure

How to avoid it

• match your answer length to marks
• use a simple structure: Point → Evidence/Reason → Link back
• keep each paragraph focused on one idea
• stop once you’ve covered the required points

7) Weak exam technique in English

English papers can punish students who don’t follow the task format or who skip planning.

Common mistakes

• missing purpose and audience in directed writing
• weak paragraphing
• repeating the prompt instead of developing ideas
• running out of time due to no planning
• vague analysis in literature answers

How to avoid it

• spend 2–3 minutes planning
• write clear topic sentences
• stick to tone (formal, persuasive, informative)
• practise under timing and self-mark using band descriptors

8) Not using the mark scheme language in Sciences

Students often know the concept but use wording that isn’t creditworthy.

What this looks like

• using everyday terms instead of scientific terms
• writing explanations that are correct but too vague
• missing key words like “increase”, “decrease”, “because”, “leads to”

How to avoid it

• build a list of mark-scheme phrases per topic
• after marking a past paper, rewrite your answer in exam wording
• practise short, precise definitions

This is where IGCSE online tutoring can help, because a tutor can correct phrasing quickly and show what earns marks.

9) Skipping diagrams, labels, and units

Marks are often awarded for clear labelling and correct units, yet students forget them under pressure.

How to avoid it

• in Biology: label diagrams neatly, use straight lines, correct terms
• in Physics: always write units, check conversions (cm to m, g to kg)
• in Chemistry: write state symbols only when required, balance equations properly

Make a personal checklist: labels, units, rounding, final statement. 

10) Not checking answers properly

Many students finish and sit quietly, or they “check” by staring at the page. Checking needs a method.

How to avoid it
Use a 5-minute checking routine:

• re-read every question quickly to confirm you answered what was asked
• check calculations where you used many steps
• confirm units and significant figures
• scan for missed sub-parts (a), (b), (c)

Even one corrected error can shift your grade.

11) Practising papers without fixing mistakes

This is the silent reason some students do many papers but don’t improve.

How to avoid it
Use a simple loop:

1. timed attempt
2. strict marking
3. Error Log entry
4. redo wrong questions
5. do 5–10 similar questions
6. retest after 2–3 days

That last step (retest) is where the score jump happens.

12) Leaving preparation too late

IGCSE success is built through repeated practice, not a last-minute sprint. Students who start early don’t just learn more, they stress less and write better.

How to avoid it

• begin past paper sections weeks before exams
• revise weak topics weekly, not once
• track progress through an Error Log
• keep a steady routine rather than long cramming sessions

Final thought

Most IGCSE marks are lost not because students lack ability, but because small habits are missing: reading carefully, matching command words, showing working, structuring answers, and correcting mistakes properly. Fix those habits through timed practice and consistent corrections, and improvement becomes predictable.

If you want, I can also turn this into a sharper, more SEO-led version targeted to parents or students looking for IGCSE online tutoring, with a stronger internal heading structure and subject-specific sections.