by Chris Woodford. Last updated: February 17, 2013.
Explain that Stuff is a fun and friendly guide to the science that powers the world around
us. Although it's mainly designed for informal self-learning, it can
also be used to support formal teaching and home-schooling across the physical science curriculum
for ages ranging from about 10 upward. It can be used by motivated
students working independently, teachers planning classes and devising
activities, and home-schooling parents working in partnership with
children. This guide is designed to help you get the most from our site
by showing how our articles map to a typical science curriculum.
Photo by Charles Oki courtesy of US Navy.
How to use this guide
There are many different science curricula in use around the world, and it's impossible to
detail how a large website like this (with over 450 long articles) maps to all of them.
Instead, I'm going to work through one typical curriculum document,
highlighting the topic areas we help to cover and noting the relevant articles from our site
that support the curriculum in each case. I've chosen to use the English National Curriculum for Science [PDF]. Don't worry that it's a UK document; it's clearly written and works well as a simple framework.
Please note that this website is not meant to be an educational textbook, so it doesn't slavishly follow the curriculum,
ticking off each subject in turn; some areas (physical sciences—and
physics in particular) are very well covered (because that happens to
be my specialism), while others (such as life and earth sciences) are
intentionally not covered at all. Please also be aware that there are many more
articles on the website that cover fascinating topics you won't find on most
public school curricula (such as computing,
and the history of technology and
inventions). If you're a parent supporting
your child at school or a home-schooler, be guided by the curriculum
but don't be overly constrained—and certainly explore beyond it if your
students show interest.
How you can use our articles for teaching and learning
Although some of our articles are strongly geared
to recognizable scientific topics like light,
energy, or magnetism,
many of them introduce science "by the back door"—taking a
familiar everyday object and carefully explaining how it works.
One of the big complaints children have about science is that they
don't see its relevance to everyday life; our articles help
to address this using copious, familiar examples that package science
in a friendly, relevant, and engaging way.
Teachers have been using our articles in many
different ways. Some simply recommend articles as initial preparation
or follow-up background reading for a deeper class activity or study.
Others suggest students pick a favorite topic from a list of articles
and write a short summary in their own words; that's a good way of
making sure information is properly absorbed and digested.
Another possibility is to ask pupils if they can figure out
how an object or an appliance works, then show them the real
explanation in the appropriate article. Or you could challenge them
to invent the proverbial "better mousetrap": ask them to list the pros and cons of one of their favorite
gadgets or inventions and then see if they can come up with something better.
If you're a home-schooling parent following a
curriculum, one good approach is to look at the articles that support
a particular topic area and work through one or two of them with your
child. For example, if you're home-schooling a 12 year-old and
studying electromagnetism, you could ask your child to make a list of
gadgets and appliances around your home that use electricity and
magnetism. Once that's done, pick one very familiar appliance—maybe
an electric doorbell,
or an electric guitar—and study it together. Read
the article on our website, discuss what's going on inside the
appliance, and relate it to the one you have in your own home.
Which grade levels we support
The Wikipedia article on Educational stage is a
good overview of the different grade levels in different
countries and how they map to one another. Broadly speaking, this
website supports curriculum learning for ages 11–18 (US grades 6–12,
UK keystages 3–5), though bright pupils below age 11 will be able to
tackle some of the simpler articles (and most articles will be of
interest to adult readers too). Our A-Z index of articles has a
simple traffic-light color-code rating showing articles that are
simple to read, ones of average difficulty, and a handful of more difficult
If you're interested in only one specific age range, you might like to skip straight to the relevant part of the notes:
Ages 7–11: Keystage 2, grades 2–6
Although our articles are not really written for children under the age of about 10, bright young students could certainly
tackle some of the simpler ones—and, of course, there's no reason why parents and children shouldn't read and work through
things together. If you're helping a younger child with homework or home study, you could read the articles we've recommended as a
backgrounder for yourself and then explain the key concepts in simpler terms your child can understand.
1. Life processes and living things
Living things in their environment
Protecting living things and their environment
For this age group, concrete examples of environmental problems and solutions work better than abstract ideas.
So you'll find it easier to work with familiar topics like pollution and recycling than with more abstract ideas like
environmentalism, which can be discussed with older students.
- Pasteurization: A simple, illustrated explanation of how a pasteurizer works and a brief biography of Louis Pasteur.
2. Materials and their properties
There are numerous articles on our site exploring
all sorts of simple materials (wood, metals, glass, plastics), as
well as not-so-simple ones (alloys, composites, and self-healing
materials). For younger age groups, the emphasis should be on
recognizing different materials, understanding the similarities and
differences between them, and appreciating that the properties of
different materials make them suitable for different uses.
Grouping and classifying materials
- Glass: The basic manufacture and uses of glass.
- Metals: Introduces the difference between metals and nonmetals and links to our detailed articles covering everyday metals.
- Paper: What is paper and how is it made?
- Plastics: How and why we use plastics, their advantages and drawbacks.
- Rubber: Includes a discussion of how vulcanization makes rubber more useful.
- Wood: Explains how we grow, harvest, and use wood.
Other interesting types of materials
- Ceramics: Introduces ceramics and their hugely diverse everyday applications.
- Composites and laminates: Although the concept of "composite" presented in this article is too complex for younger children, you could certainly explore the idea of combining materials in simple ways to make stronger ones. For example, most children of this age will come across things like papier maché, which is essentially a composite based on paper,
textiles (sometimes), and adhesive. Most of us also learn how to strengthen things like book covers with self-adhesive plastic, which is an example of making a laminate.
- Protective materials: Another way to teach materials science is to start from spectacular or dramatic applications and work back to the materials that make them possible. "What sort of clothes would we need to protect us against fire? What might you need to wear for a trip into space?"—those are options you could explore.
Properties of materials
- Materials science: An introduction to the idea that the inner structure of a material gives it unique properties that make it suitable for a particular job. This is another complex topic, but you can gear it to almost any age group. For example, it's easy to break apart something like a twig and show how the layers of wood give it more strength in one direction than another.
In another simple activity, you could get students to measure the temperature of different materials then see
how hot or cold they feel; explain that materials at the same temperature can feel hotter or colder because of
different rates of heat conduction related to their internal structure.
- States of matter: How a material can change form (state) when the temperature or pressure changes.
- Drilling: A simple look at hardness (including the Mohs hardness scale), which is easy to cover in a practical activity.
- Candles: Exploring the idea that a candle is a miniature chemical factory that uses combustion to turn wax into light and heat energy.
- Clothes dryers: Ordinary states-of-matter science can be dull, so why not teach it by exploring the science of drying clothes by evaporation? There's plenty of scope for practical experiments drying clothes in different ways (for example, weighing wet clothes and timing how long they take to dry under different conditions).
- Thermometers: You can measure temperatures by observing the way
heat energy makes materials expand or contract in thermometers.
Separating mixtures of materials
- Water filters: Explains how various water filters separate out impurities. (This article touches on things like ion exchange and osmosis that are too complex for this age group, but the basic idea of water filtering is a good, familiar everyday application and something you can easily demonstrate at home or in class. For younger students, concentrate on simpler, physical filtration with sieves or filter paper.)
3. Physical processes
This is our first simple introduction to physics: electricity, light, sound, and basic forces. For this age
group, it's good to keep things concrete and practical. Focus on safe
hands-on experiments with electricity (simple practical electric
circuits with lamps and batteries), magnetism, light, and sound;
there are plenty of examples of things around the home that use all
four. Make sure that you relate forces to easy-to-understand ideas
like weight and falling (don't get bogged down in abstract ideas of
what forces are or how they "act at a distance").
- Electricity: Introduces electricity, explains how it's made, and describes electrical and electronic circuits.
- Batteries: Explains how a battery makes power using finite chemical reactions.
- Intruder (burglar) alarms: A simple series circuit you can build with a flashlight battery and lamp.
- Electric doorbells: A slightly more complex electromagnetic circuit.
Forces and motion
Light and sound
- Light: Introduces what light is, how it travels, and basic properties such as reflection and refraction.
- Mirrors: Explains how mirrors work by reflection and compares different types.
- Sound: Explains that sound is a type of energy caused by vibration, how it travels, and how we hear things.
- Pianos: A simple explanation of a very unconventional string instrument.
- Record players: Although dated, still a classic example of how vibrations make sound.
Other topics for younger students
The articles flagged in green on our A-Z index are best for younger readers.
Simpler articles popular with this age group include:
Ages 11–14: Keystage 3, grades 6–8
1. Life processes and living things
Living things in their environment
We learn that humans and the environment are interdependent, how the environment can be protected, and the
importance of sustainable development. For this age group, we can start to explore different types of pollution and touch on some of
the controversies of environmentalism (for example, is it always worth recycling things or is it sometimes better to treat waste in
- Air pollution: What gases do you find in air pollution and where do they come from?
- Composting toilets: Toilets pollute almost by definition, but composting toilets put waste to better use. There's an opportunity here to discuss the idea of environmentalism as a way of taking responsibility for yourself and your impact on the planet.
- Eco-homes: The focus here is on cutting-edge eco-friendly buildings, though you could ask students to explore their own homes, making lists of things that seem particularly unfriendly. Can they think of simple ways of reducing those impacts?
- Environmentalism: This is a more wide-ranging, discursive article about the philosophy of environmentalism. You could balance it with a discussion about the economic pressures on the environment. Should economic and environmental factors be in conflict? Are there ways to reconcile them?
- Land pollution: We tend to focus on air and water pollution, which is much more obvious than land pollution. If you'd like a change from oil slicks and smokestacks, start here!
- Renewable energy: Briefly introduces and compares the main types of renewable energy (biomass, wind, solar, and so on). We have separate articles about each of these if you want to explore more deeply.
- Recycling: Includes an introduction to recycling different materials and a critical look at whether recycling is always the best method of disposal.
- Water pollution: The causes, effects, and solutions of water pollution (including marine pollution).
2. Materials and their properties
We begin to understand how different materials have different properties and how a substance such as water can exist
in different states at different temperatures and pressures. Although we have few articles about chemistry, some of our articles do touch
on states of matter, the properties of materials, and changes of state.
Solids, liquids, and gases
- States of matter: The basic difference between solids, liquids, and gases in terms of the particles from which they're made. How and why materials change state.
- Heat energy: What is heat and how does it move from place to place by conduction, convection, and radiation?
- Water: An overview of its main properties and how they relate to its internal, molecular structure.
- Barometers: Compares Torricellian and aneroid barometers.
- Refrigerators: You can relate the changing state of the coolant (back and forth between liquid and gas) to the energy transfer taking place between the refrigerator and the room outside.
- GORE-TEX® waterproof clothing: This familiar everyday example shows how the concept "changes of state" explains waterproof textiles that are waterproof and breathable at the same time.
Elements, compounds, and mixtures
- Atoms: A basic introduction to atoms and their structure. How does one atom lead to the next?
- Nanotechnology: This article reinforces the idea that atoms are material building blocks.
- Materials science: How the inner structure of a material gives it useful properties.
- Metals: An overview of metals that links in to our more detailed articles about the more common metals (including aluminum, copper, gold, iron/steel, nickel, silver, titanium, tungsten, and zinc).
- Separation techniques:
- Chromatography: An introduction to paper, liquid, and gas chromatography. For this age group, you'll probably want to focus on paper chromatography, but it does no harm to mention things like gas chromatography and perhaps
touch on its practical use in such things as forensic science.
- Centrifuges: Although this article focuses on the physics of spinning and the difference between centripetal and centrifugal force, centrifuges are mentioned as practical applications.
- Mass spectrometers: A relatively simple overview without too many technical details.
- Vacuum cleaners: An everyday application of (air) filtering that will mean more to students
than laboratory-style filtering.
3. Changing materials
This area explores physical, chemical, and geological changes.
Chemical reactions and effects on the environment
4. Patterns of behavior
Mostly focused on chemistry, this area explores metals and their simple reactions. It also introduces acids and bases, measuring acidity and alkalinity, and everyday chemical reactions. Although there's relatively little
chemistry on our website, we do have articles covering most common metals and how pH meters work.
- Metals: An overview of metals and their properties (compared to those of nonmetals). Includes links into our more detailed articles on specific metals.
Acids and bases
- pH meters: This is quite a detailed article about the workings of pH meters that younger students may find too complex. But it might be worth touching on pH meters in passing if students question the vagueness of working with
crude litmus tests.
5. Physical processes
The core of the physics part of the curriculum, this section introduces fundamental physics concepts like electricity, magnetism, forces, light, and sound. As with younger age groups, these topics are still best introduced through concrete examples such as everyday electric circuits (flashlights, intruder alarms, doorbells).
Electricity and magnetism
What are electricity and magnetism, how are they connected, and what practical use are they?
- Electricity: An overview of electricity, including how it relates to electronics, how we produce electricity in different ways, and how we measure things like electric currents and power consumption.
- Batteries: How does a battery make electricity through chemical reactions?
- Magnetism: An overview of magnetism and its uses, including domain theory and simple atomic explanations.
Examples of electromagnetism
There are plenty of everyday examples of how electricity and magnetism work hand-in-hand; it's great to explore and compare different electromagnetic appliances in the home.
- Electric doorbells: Looks at simple switches and temporary electromagnets in circuits.
- Electric guitars: Focuses on how electromagnetic pickups work in guitars.
- Electric motors: An illustrated guide to how electric currents make motors spin.
Older students could also cover generators.
- Loudspeakers: How electricity and magnetism work together to make sound.
- Microphones: The opposite of loudspeakers, they turn sound into electrical
- Headphones: Includes the theory of how headphones work and photos showing how they're put together in practice.
- Intruder (burglar) alarms: A simple example of an electric circuit or two circuits linked together.
- More advanced examples:
- Metal detectors: How electromagnetic coils can detect hidden metal objects.
- Moving-coil meters: How electromagnetism can be used to measure the voltage or current in a circuit.
- Relays: How can a tiny current switch on a much bigger current in something like a telephone exchange?
- Transformers: How can you convert a big voltage into a small one (or vice-versa)?
Forces and linear motion
In this section, we learn how pushing and pulling forces sometimes produce motion and sometimes don't and how the size
of a force relates to the amount of motion it produces.
Dynamics (unbalanced forces)
By this stage, students are starting to explore motion in a quantitative way.
- Motion: Covers Newton's three laws of motion. Although most of our articles contain little or no math, this one covers the simpler equations of motion as they relate to definitions of speed, velocity, acceleration, momentum, and kinetic energy.
(You could use Jet Ski® and Sea-Doo® or
propellers as an example of Newton's laws.)
- Pedometers: If laws and equations of motion seem too abstract, this is one concrete example you could explore.
- Pendulum clocks: A slightly more complex example relating energy conversion to time.
- Speedometers: A good way to link electromagnetism to studies of speed and motion.
- Brakes and parachutes: Explain the idea of stopping movement by dissipating energy with friction (heat) and air resistance.
- Simple machines: Covers classic topics like levers, screws, and so on. We also
have separate articles on gears, pulleys,
and wheels and axles.
- Drilling: A box in the middle of this article explains the science of drills, putting concepts like force, energy, and hardness into a familiar everyday context.
Statics (balanced forces)
- Buildings: You can explain that buildings stay upright when forces balance and collapse when they don't. You could compare different situations where buildings have collapsed (by natural disaster, acts of terrorism, or deliberate demolition) and consider where the forces have come from in each case.
- Bridges and tunnels: Bridges are a great way to explore static forces. The diagram near the start of our article explains how different parts of a bridge are in either tension or compression (terms which have been introduced in our article about buildings).
- Hot-air balloons, boats and ships,
and submarines are an opportunity to explain buoyancy and floating.
- Weights and balances: Explores the distinction between weight and mass. Note the considerable scope for confusion if you learn or teach this using Imperial units such as pounds; it's much better to learn about metric SI units from the start.
- Pendulum clocks: It's good to explore the idea that pendulum clocks run at different speeds in different places.
- Center of gravity: Why do things topple over if they're not balanced?
Frictional forces and air resistance
- Aerodynamics: You need to relate air resistance to friction with care—and I prefer to keep them quite separate: air resistance is more obviously related to other aerodynamic concepts, while friction is more closely related to subjects like
adhesives and lubrication. Our main aerodynamics article explores aerodynamic concepts suitable for older students, but the simpler topics can be covered with younger students.
- Bullets: A concrete example of how air resistance makes a big difference to how things travel. The box at the end of the article explains how drag slows a bullet's motion.
- Lubricants: A simple look at how lubrication reduces friction.
- Nonstick pans: Although mostly about adhesion and sticking, there's some friction here too. You could explain that PTFE, the nonstick chemical used on cookware, is also used as a non-liquid lubricant.
Force and rotation
- Centrifuges: We explore centripetal and centrifugal force as two different ways of describing the same basic phenomenon.
- Flywheels: Introduces the idea that rotating objects store energy. This article is based on concepts like moment of inertia and is really intended for older students.
Force and pressure
- Hydraulics: A simple, illustrated explanation of using incompressible liquids to magnify forces. There are some excellent hands-on hydraulic activities you can do with students using simple medical syringes and tubes linking them together.
- Autoclaves (which includes pressure cookers) and memory foam mattresses (which covers the "bed of nails") are everyday applications of force and pressure.
- Gas springs: If you're teaching gas springs, be sure that students are clear on the distinction between a bicycle pump and a gas spring; it's quite easy to confuse the two.
- Pumps and compressors: How we can move liquids and gases from one place to another. It's worth exploring the difference between liquid pumps (usually transporting liquids at a constant pressure) and gas compressors (that work by squeezing air into less volume). You could also explore the difference between pneumatic machines like jackhammers (pneumatic drills), which are powered by air compressors, and hydraulic ones.
- Pressure washers: A simple everyday example of pressure in action.
Light and sound
We discover that light and sound are two different kinds of energy in motion and compare their similarities and differences.
The behavior of light
- Light: A basic overview of light energy and its properties, including an introduction to color.
- Mirrors: A simple explanation of what happens inside a mirror.
- Lenses: This article explains how lenses bend light and compares concave and convex lenses, with everyday examples.
- Luminescence: Why do some things glow in the dark? Explores the different kinds of luminescence in things like glow-in-the-dark paint and creatures such as glow-worms and fireflies.
- Lasers: If you're looking for a more dramatic example of making light, look no further than lasers. However, you will need to have studied a little bit of atomic theory before you cover this so you can explain how the light is amplified.
Holograms are probably best covered with waves.
- Binoculars: An example of lenses in action. It's worth studying the focusing mechanism a little.
- Fresnel lenses: A fascinating example of how we can make super-powerful lenses. Be sure to explain why Fresnel lenses are generally of a lower optical quality than equivalent ordinary lenses.
Vibration and sound
- Sound: Be sure to compare and contrast light and sound, including why light can travel through space but sound can't.
- Synthesizers: A more interesting article about musical sound, most suitable for older readers. This explains why instruments such as pianos and guitars sound different even when they play exactly the same musical note.
- Electric guitars: You could explore the difference between acoustic and electric guitars.
- Hearing aids: The curriculum covers how we hear sounds and how
loud sounds can lead to deafness. If you've already covered microphones and loudspeakers in electromagnetism, it's worth a brief digression to explain how hearing aids can help to correct
deafness. (The second part of the article is a more technical explanation that won't be relevant for younger readers.)
The Earth and beyond
Here's an opportunity to cover some basic space science.
Energy resources and energy transfer
It can be quite hard to define energy in a scientifically rigorous way that makes sense to young students;
and it's often best to relate it to concrete everyday examples instead (the energy in food, for example, or how much energy electrical appliances use).
- Energy: What is energy, where does it come from, and will the world ever run out of it?
- Energy storage: You might compare batteries with older technologies such as flywheels. Although you'll want to focus on conventional batteries, it's also worth considering (briefly) how rechargeable batteries work if students ask the question. You can explain using the idea of reversible and non-reversible chemical reactions.
- Renewable energy: How can we make energy in a way that doesn't use up Earth's scarce resources?
Specific examples of renewable energy:
Conservation of energy
- Heat energy: What it is and how it moves by conduction, convection, and radiation.
- Central heating and gas boilers: How energy is usefully transported to heat a home.
- Law of conservation of energy: One of the most important laws of physics. The second part of our article explains why perpetual motion machines don't work, which is a fun topic you could always start off with. There's also some coverage of James Prescott Joule's ingenious experiment. Our gears article gives a specific example of how
the conservation of energy governs the way machines work.
- Ways in which energy can be transferred:
- Ways in which energy can be stored:
Ages 14–16: Keystage 4, grades 9–10
This is a much more challenging age group: students
at this level study the same broad areas of science but in somewhat
greater depth, taking a more quantitative, critical approach, and
questioning the limits of science. It's particularly important that
we take more trouble to explain to older students why science is relevant
and worth their time. Surveys in the UK show that almost half of nine year-olds
enjoy science because they think it will be useful in life, while only 35
percent of 14-year-olds share that view. Keep things engaging
using plenty of familiar, everyday examples!
1. Life processes and living things
Living things in their environment
While younger students may have a fairly
black-and-white view of environmental issues (pollution is always
bad, recycling is always good), older students can explore the gray
areas too. Why has pollution happened and could it ever be
justified if it led to economic gains that helped to reduce
poverty or improve health? Does pollution affect different social
groups disproportionately? Is sustainable development an achievable
- Pollution: It's worth comparing air, land, and water pollution instead of tackling just one of them. You could
consider the different ranges of each and note that air pollution is more of a transboundary problem than
water or land pollution. You could also explore connections such as how air pollution becomes land or water
pollution through atmospheric deposition.
toilets: How can you dispose of sewage without causing
- Eco-homes: It's worth exploring the idea that most of us live in older homes and seeking ideas on how those can be made more eco-friendly through insulation or retro-fitted green technologies like
- Environmentalism: What is environmentalism and what does it involve?
- Fair trade: Why should we care where our products come from? Although not strictly science, it's worth incorporating some consideration of social justice into any discussion of environmental issues. How are people related to the environment? How does alleviating world poverty connect with issues like protecting the environment?
- Organic food and farming: This is a fairly critical look at the claimed benefits of organic growing, so it's most suitable for older students.
energy: How can we make energy in a way that doesn't
use up Earth's scarce resources?
- Recycling: How can we reduce our impact on the planet by trashing less and
reusing more? A box in this article briefly explores the critical viewpoint that recycling is an ineffective "feel-good gesture".
Although that's well worth exploring with older students, be sure to consider the evidence and statistics; don't
simply polarize the debate and reinforce existing opinions.
2. Materials and their properties
Younger students learn that different materials have
different properties; older students can begin to relate these
properties to the inner structure of different materials. Materials
science is very easy to present in a dull way, so choose interesting and dramatic examples (superglue,
self-healing materials) to make the point.
- Atoms: How atoms differ in their numbers of protons, neutrons, and electrons. At this age, students can start to explore different models of atomic structure and consider how different arrangements of electrons give rise to different chemical properties.
- Materials science: What makes one material different from another and better for a particular job?
- Television: Can be used as a familiar example of an electron tube, although CRT televisions are now becoming so rare that the example will mean less to younger students than it used to.
Some everyday examples of how we use physical changes in materials to do useful jobs:
- Thermostats: How expanding and contracting metals can help to regulate temperatures.
- Thermocouples: How we can measure temperature using changes in electrical conductivity.
- Aerosol cans and fire extinguishers: Explain how pressurized substances escape.
- Pumps and compressors explains how we use pressure to move liquids and gases from place to place along pipelines.
- Jackhammers (pneumatic drills): How useful machines can be powered by compressed air.
- LPG (liquified petroleum gas): How we can pack more energy into less space.
- Water: The fascinating properties of water and how they stem from its polar molecular structure.
- Non-newtonian materials: Although it's not on the basic curriculum, this an interesting topic that will certainly engage young scientists: everyone wants to know why you have to shake ketchup and why you can walk on custard! We explain in the context of energy-absorbing plastics, but you don't have to.
- Shape-memory alloys: A more complex example that might appeal to older students.
Useful products from organic substances
- Nylon: An interesting everyday example of a polymer. Also worth relating it to super-strong
Kevlar® and fireproof Nomex®.
- Paint: What do paints contain? Are they harmful?
- Plastics: What makes plastics so versatile?
- Bioplastics: Can we create environmentally friendly plastics?
- Harmful products of burning hydrocarbons:
global warming and climate change could be considered here. So could
carbon monoxide detectors (one of the more harmful byproducts of combustion and how we can detect it for our own safety).
- Graphene: A topical example of carbon chemistry.
Useful products from metal ores and rocks
- Metals: Introduces and compares different metals and nonmetals.
- Alloys: Explains the basic concept of an alloy, compares substitution and interstitial alloys,
and lists common everyday alloys in a table.
- Bricks: A simple overview of brick and building technology.
- Ceramics: Although this topic can seem dull, there are many interesting everyday applications of ceramics—and that's probably the way to tackle it.
Changes to Earth and the atmosphere
- Air pollution (introduction): An overview of its causes, effects (environmental and human), and solutions.
- Electrostatic smoke precipitators: It's good to link this topic into static electricity.
- Global warming and climate change: This can become contentious, so keep a clear distinction between the science and the politics. It's worth asking older students to explore the controversies and why global action has so far been limited.
- Geoengineering: Although not a curriculum topic, you could certainly touch on this when you explore solutions and adaptations to climate change.
3. Patterns of behavior
Although our site contains relatively little chemistry, there are two articles on neon and xenon lamps (illustrating
examples of how noble gases can be used) and a number others covering everyday metals (including their basic chemistry, extraction, and common uses).
The periodic table
- Atoms: A basic overview of atomic structure:
- Neon lamps: Explains how different colors are made and relates that to quantum leaps inside atoms.
- Xenon lamps: A box at the end touches on the noble gases.
- Elements we cover with individual articles:
- Fireworks: Explores the chemical reactions that make different fireworks different colors and uses physics concepts such as conservation of momentum to explain the symmetry of explosions.
Rates of reaction
- Catalytic converters: A simple example of catalysts. You could also relate this to the environmental part of the curriculum (up above).
- Zeolites: Catalysts are often taught in a very abstract way that's hard to relate to. As an alternative, why not talk specifically about zeolites? It's easy to picture them and explain how the cage structure gives them particular useful properties in things like ion-exchange water filters and chemical catalysts.
- Self-cleaning windows and
photocatalytic air purifiers are two cutting-edge
examples of catalysts doing useful, everyday jobs in the home.
Reactions involving enzymes
- Detergents: This article explains the basic cleaning action of detergents, but also touches on the enzymes found in washing detergents and what they do. One way to frame a lesson around detergents is to explore the label on a typical packet or bottle of clothes washing detergent. Try to choose one carefully with a minimum of complex-sounding ingredients; gloss over any ingredients that don't seem obviously relevant. (Eco-friendly products might be good ones to go for, since they minimize the number of active ingredients.)
4. Physical processes
This section extends the same basic physics topics
we've covered for younger age groups. School physics textbooks have a
tendency to run through a list of abstract-sounding areas (forces,
energy, motion, waves...) that may have no apparent relevance to
everyday life, so try to tackle the material in a familiar, everyday
context. For example, you can teach quite a lot of the basic physics
of waves by talking about surfing; sport (including swimming) is a
great way to introduce forces and motion; and there are plenty of
everyday examples of things like static electricity (photocopiers,
laser printers, and power station pollution scrubbers). Remember:
students of this age are questioning the relevance of studying science to
their lives, so keep it concrete, engaging, and interesting!
Students of this age are starting to explore more complex circuits and will need to
understand the distinction between basic electricity (a simple source of energy)
and electronics (a way of controlling electricity).
- Electricity: An overview of electricity and how we use it.
- Fuses: How surge protectors and fuses protect electrical equipment.
- Heating elements: How we can convert electrical energy into heat. Examples
are developed in more detail in these articles:
- Energy monitors: Make sure students understand that different appliances cost different amounts of money to run—and why. It's great if you can get hold of some monitors and get students measuring energy use either in their own homes or at school. It's also worth calculating the cost of running appliances from the raw power (wattage) figures and comparing. Why might the two figures (the actual and theoretical measurements) be different?
- Static electricity: This is a slightly more involved explanation of static electricity (in terms of triboelectricity) that will satisfy students wondering where static charges come from when they rub things.
- Practical everyday static electricity:
- Electrolyzers: This article relates electrolysis to things like
hydrogen fuel cells and electric cars.
You'll also want to relate them to batteries.
You could cover electroplating as another practical application.
- Piezoelectricity: Our article includes a simple animation.
Forces and motion
Force and acceleration
- Motion: Introduces speed, velocity, acceleration, momentum, and kinetic energy and relates them to Newton's laws.
- Accelerometers: Now many students have cellphones and games consoles that contain accelerometers, this topic is a good way to explore Newton's second law.
- Speedometers: How can we measure speed accurately? This is an interesting application of electromagnetism (eddy currents).
- Sport: The science of sports is an interesting way to introduce the physics of motion to students who might not otherwise see its relevance. You could start a lesson by asking students about their favorite sports, then spelling out
how science can help to improve their performance.
- Swimming: Can physics make you a better swimmer?
- Adhesives: Explains the difference between adhesive and cohesive forces and why geckos can climb walls.
Characteristics of waves
- Light: An introduction to light and its properties (reflection, refraction, diffraction, and interference).
- Sound: What is sound and how does it travel?
- Surfing: An engaging example of where waves come from and how they travel.
- Synthesizers: How waves of different shapes and sizes make unusual sounds, including hands-on activities.
- Holograms: Good examples of using wave interference.
The electromagnetic spectrum
- Electromagnetic spectrum: A broad-brush overview of the spectrum and the familiar bands of electromagnetic waves.
- Space telescopes: This article looks at telescopes and satellites that sense all kinds of electromagnetic radiation, which is a great opportunity to explore electromagnetic radiation in a very concrete, visual way. You can also make the (philosophical) point that the world is much more than the world our eyes can detect with visible light
- Microwave ovens: The focus is mostly on how ovens work, but you can use it to highlight the energy that waves contain.
- Radio: How long waves carry information around our world. If you want to make the topic more relevant to teenagers, you could cover cellphones (Mobile phones) as well (or instead).
- Antennas and transmitters: How do we send and receive radio waves from one place to another?
- X rays: A short introduction and history.
- Infrared remote controls: A fairly simple example of electromagnetic radiation put to good use.
- Analog versus digital technology: A simple explanation of the differences between
analog and digital and their advantages and disadvantages. Includes a box on music sampling.
- More advanced topics:
- Fiber optics: How does light travel down glass and plastic cables?
- Satellites: Why do we send communications signals into space?
- Radar: How we can use radio waves to locate hidden objects, measure speeds, and forecast the weather.
- RFID tags: A familiar everyday example of radio waves used in shop security and automatic library checkout machines.
- Sunscreen: Explores the harmful effects of ultraviolet radiation and how we can reduce them.
- Invisible ink and energy-saving fluorescent lamps
and night vision goggles are interesting examples of how invisible electromagnetic radiation can be converted into visible light.
Sound and ultrasound
- Sound: An overview of sound and how it travels.
- Ultrasound: A simple introduction plus everyday examples, including medicine, nondestructive industrial testing, and sonar.
- Noise-cancelling headphones: A fun example of constructive and destructive interference.
- Earthquakes: What causes earthquakes and how seismic waves travel. How can we protect buildings from earthquake damage?
Energy resources and energy transfer
- Heat energy: How heat moves from hotter to colder objects.
- Heat insulation, vacuum flasks,
and wetsuits are everyday examples of how insulation slows heat losses.
- Law of conservation of energy: Why we can't create or
destroy energy and why perpetual motion machines never work.
- Heat pumps: Ground-source, geothermal pumps are an interesting example of apparently getting energy for free. It's very important to explain why heat pumps don't violate the law of conservation of energy.
- Bicycles: This explores the science of bikes, including how they use energy and why they are so efficient compared to other machines (and other forms of transportation).
- Heat-reflecting (low-E) windows: A more advanced example of reducing heat energy losses in the home.
- Regenerative brakes: A topical example of how vehicles are trying to recycle energy normally wasted in braking.
- Energy saving: How can you save energy at home, at work, and when you travel?
Work, power, and energy
- Atoms: A basic overview of atoms and isotopes.
- Geiger counters: How can we detect ionizing radiation?
- Smoke detectors: A good example for students who struggle to see the relevance of radioactivity to everyday life.
Obtaining and presenting evidence
We have many articles covering scientific instruments and test equipment,
- Great physics experiments: Why not inspire students with great experiments from the past? You probably won't want to cover them all at once, as I have, but you could work them into appropriate points in your study program.
Older students (ages 16–adult)
For older students, the curriculum becomes richer, deeper, and more diverse and there's a
greater emphasis on critical thought and self-study. Older students
will begin to encounter interdisciplinary sciences like psychology,
which combine widely different aspects of the earlier curriculum.
From the feedback I get from high school (A-level) students, it's pretty clear
that students of this age have reached the stage where they can pick
and choose articles that are most relevant to the topics they want to
study, and I'm not going to offer specific recommendations. One area
where older students like to use our articles is for background reading
in preparation for things like science, engineering, and inventing
contests. For example, if you're going to develop some kind of gadget
that uses trip switches, you could learn how they work in our
background articles about reed switches or Hall-effect sensors before
setting out on your own experiments.
Older students who are starting to think about science careers (or science as a fun hobby) might like to explore
our article on how to be a scientist.