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What science is—and what it is not

Hypothesis, theory and law: the differences

Why science uses standard units

Accuracy, precision and measurement uncertainty

Why scientists use models

Correlation and causation are not the same thing

Peer review, replication and scientific confidence

How to evaluate a science claim

Motion, speed and acceleration

Forces and Newton's laws in everyday motion

Gravity from falling objects to orbits

How friction makes motion possible—and resists it

Pressure in air and liquids

Energy: forms, storage and transfer

Conduction, convection and radiation

How insulation slows heat transfer

How sound waves work

Light and the electromagnetic spectrum

Reflection and refraction

Why the daytime sky looks blue

How rainbows form

Colour: light, pigments and perception

Lenses, magnification and cameras

Electricity and basic circuits

Magnetism and electromagnets

How batteries store and deliver energy

Atoms, molecules and chemical bonds

How the periodic table organizes elements

What happens in a chemical reaction

Acids, bases and pH

Why water has unusual properties

Why water expands when it freezes

Surface tension, droplets and soap bubbles

How soap and detergents work

How adhesives stick

Why glass is transparent—and why it can break

Polymers and plastics

The science of textile fibres

Fragrance, volatile molecules and smell

The science of fermentation

How heat transforms food

What the Maillard reaction is

Why oil and water can form emulsions

How leavening makes baked foods rise

How the water cycle moves water around Earth

How clouds form

How air pressure relates to weather

Humidity, relative humidity and dew point

Weather and climate: different time scales

Why leaves change colour in autumn

How photosynthesis stores solar energy

Plant growth: light, water, carbon and mineral nutrients

Bacteria and microbes in everyday life

Immune memory and how vaccines use it

Circadian rhythms and the daily biological clock

Why Earth has seasons

How stars form

The life cycle of a star

Understanding the scale of the solar system

Why the Moon has phases

Why telescopes observe different wavelengths

How everyday electronics use semiconductors

How capacitive touchscreens detect a finger

How refrigerators and heat pumps move heat

How modern clocks keep time

The science behind bridges

What recycling can and cannot do to materials

Biodegradable and compostable materials are not the same thing

How Science Works

Chemistry & Materials

Earth & Life

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