CAIE IGCSE science revision — structure, content, and how to prepare

Cambridge IGCSE science, offered by CAIE (Cambridge Assessment International Education), is taken by students in international schools and UK independent schools. It differs from AQA and Edexcel in its exam structure, its core and extended content split, and the way practical skills are assessed. Students who understand these differences before they start revising can target their time much more precisely.

CAIE IGCSE science structure

Separate sciences

CAIE offers IGCSE Biology (0610), Chemistry (0620), and Physics (0625) as separate qualifications. Each has multiple paper options, and schools choose their combination.

Core and Extended content

The most important structural distinction in CAIE IGCSE science is the core and extended split:

• Core content leads to grades C–G and is assessed in Papers 1, 2, and 3
• Extended content (which includes all core content plus additional material) leads to grades A*–E and is assessed in Papers 1, 3, and 4

Students taking the extended route must know all of the core content as well as the additional extended sections marked in the specification with a different symbol.

Paper types

The most common paper combination:

• Paper 1 — multiple choice, 45 minutes (core content)
• Paper 2 — multiple choice, 45 minutes (extended content)
• Paper 3 — theory paper, core, 1 hour 15 minutes
• Paper 4 — theory paper, extended, 1 hour 15 minutes
• Paper 5 or 6 — practical assessment or alternative to practical

Some schools also enter students for Paper 6 (the alternative to practical paper), which tests practical skills through data analysis and planning questions on paper rather than in a lab.

Practical assessment and Paper 6

CAIE IGCSE science places significant weight on practical skills. Students who do not have access to a lab setting (or whose school uses the alternative route) sit Paper 6, which includes:

• planning an experiment
• interpreting data from a results table or graph
• identifying sources of error and suggesting improvements
• drawing accurate graphs with labelled axes and appropriate scale

Paper 6 is often underrevised. Students who practise planning questions and graph-drawing separately from content revision tend to do significantly better than those who treat Paper 6 as a last-minute addition.

CAIE IGCSE biology — key content areas

Core and extended Biology topics include:

• Cell biology — animal and plant cell structures, diffusion, osmosis, active transport
• Enzymes — active site, optimum pH and temperature, denaturation
• Nutrition and digestion — enzymes, food tests, the alimentary canal
• Respiration — aerobic and anaerobic equations, the role of mitochondria
• Gas exchange — alveoli, leaf structure, stomata and guard cells
• Transport — blood cells, blood vessels, the heart, transpiration, phloem and xylem
• Reproduction — sexual and asexual, the menstrual cycle, germination
• Genetics — DNA, chromosomes, Punnett squares, mutation, natural selection
• Ecology — food webs, nutrient cycles, the carbon cycle, human impact

Extended-only additions include genetic engineering, the nitrogen cycle in depth, and hormonal coordination.

CAIE IGCSE chemistry — key content areas

Core and extended Chemistry topics include:

• Atomic structure — proton, neutron, electron; atomic and mass number; isotopes
• Bonding — ionic and covalent bonding; dot and cross diagrams; properties
• The periodic table — groups 1, 7, and 0; trends in reactivity
• Chemical equations — word equations, symbol equations, balancing
• Quantitative chemistry — relative atomic mass, mole concept, concentration
• Acids and bases — pH, neutralisation, salt preparation
• Rates of reaction — collision theory, factors affecting rate, catalysts
• Electrolysis — products at each electrode, industrial uses
• Organic chemistry — alkanes, alkenes, addition polymerisation, ethanol production

Extended-only topics include: enthalpy changes, equilibria, further organic chemistry (carboxylic acids, esters), and analytical chemistry in more depth.

CAIE IGCSE physics — key content areas

Core and extended Physics topics include:

• Motion — speed, velocity, acceleration, distance-time and velocity-time graphs
• Forces — Newton’s laws, weight and mass, pressure
• Energy — forms of energy, energy transfer, efficiency
• Thermal physics — states of matter, specific heat capacity, specific latent heat
• Waves — properties, reflection, refraction, the EM spectrum
• Sound — longitudinal waves, echoes, hearing range
• Light — lenses, reflection, total internal reflection
• Electricity — charge, current, potential difference, resistance, circuits
• Magnetism — magnetic fields, electromagnetism, transformers
• Radioactivity — alpha, beta, gamma; decay; half-life; nuclear equations

Extended-only additions include: circular motion, gravitational field strength in depth, the Doppler effect, and further nuclear physics.

Revision strategies for CAIE IGCSE science

Cambridge examiners reward students who can express precise scientific reasoning and apply concepts to unfamiliar data. The most effective revision strategies:

Practise with past papers — CAIE past papers from the last five to seven years are the best preparation. Mark your own answers against the published mark scheme, noting where marks are lost for vague language or missing vocabulary.

Use active retrieval, not passive review — reading through revision notes is far less effective than writing out processes from memory, then checking. See the guide on active recall for GCSE science for specific examples.

Space your reviews — topics covered once tend to fade. A revision timetable should revisit each topic at least once more after the initial session. See spaced repetition for GCSE science for how to build this in.

Practise Paper 6 questions specifically — graph drawing, planning, and error analysis questions need their own practice. Students who only revise theory content are often unprepared for the structure of practical questions.

Command words in CAIE IGCSE science

Cambridge mark schemes use specific command words that determine the expected answer:

• Define — give the precise scientific meaning
• Describe — state what is happening or what is observed
• Explain — give the reason using scientific knowledge
• Calculate — show all working and give units
• Suggest — apply science to an unfamiliar situation
• Compare — identify similarities and differences (both required for full marks)
• Evaluate — use evidence to make a judgement

The difference between describe and explain costs marks in every exam sitting. Practise reading command words before answering, not after. For a full guide, see GCSE science command words.

Studia and CAIE IGCSE science revision

Studia is an iPhone and iPad revision app that uses spaced repetition and retrieval practice to schedule GCSE and IGCSE science revision. Students input their exam dates and topic confidence, and the app structures sessions around what needs the most work before each paper.

For more on the app, read the GCSE science revision app guide.