Materials and Their Properties
Materials and their properties explained for primary students: what materials are, why we choose wood, metal, glass, plastic or fabric for different jobs, and how properties like hardness, strength and waterproofing matter, with a quiz.
Key takeaways
- A material is the 'stuff' an object is made from, like wood, metal, glass, plastic or fabric
- Every material has properties — how hard, strong, bendy, see-through or waterproof it is
- We choose a material to match the job it has to do, like glass for windows and rubber for tyres
- The same object can be made from different materials, and one material can be used for many things
What is a material?
Look around the room. A wooden table, a glass window, a metal spoon, a plastic bottle, a woolly jumper — every single thing is made from something. That "something" is called a material. A material is the stuff an object is made from.
It is easy to mix up two words: an object is the whole thing (a cup, a chair, a shoe), while a material is what it is made of (glass, wood, leather). The same object can be made from different materials. A cup might be made of glass, plastic, paper or metal. So before we make anything, we have to choose the right material — and to do that, we look at its properties.
What are properties?
A property is a way of describing what a material is like. Scientists test and compare materials by their properties. Here are some important ones:
- Hard or soft — a rock is hard, a sponge is soft.
- Strong or weak — steel is strong, dry paper tears easily.
- Bendy (flexible) or stiff (rigid) — rubber bends, a brick does not.
- Transparent, translucent or opaque — you can see through clear glass (transparent), partly through frosted glass (translucent), but not through wood (opaque).
- Waterproof or absorbent — a plastic raincoat keeps water out, a towel soaks water up.
- Magnetic or not — iron is pulled by a magnet, plastic is not.
- Rough or smooth, shiny or dull, heavy or light for its size.
A material usually has several properties at once. Glass, for example, is hard, smooth, transparent and waterproof — but it is also brittle, which means it can shatter.
Matching the material to the job
Here is the big idea: we choose a material to match the job an object has to do. Engineers and designers think hard about this every day.
| Object | Material | Why this material? |
|---|---|---|
| Window | Glass | Transparent and waterproof |
| Saucepan | Metal | Strong and carries heat well |
| Raincoat | Plastic or coated fabric | Waterproof and bendy |
| Car tyre | Rubber | Tough, bendy and grippy |
| Jumper | Wool or cotton | Soft and keeps you warm |
| Book pages | Paper | Light, smooth and easy to print on |
Imagine a saucepan made of paper, or a jumper made of glass — they would be useless! The job tells us which property matters most.
The same material, many jobs
Just as one object can be made from many materials, one material can do many jobs. Metal is used for spoons, bridges, coins, keys and aeroplanes. Plastic is used for bottles, toys, chairs and pens. This is because the same property can be useful in many places — metal is strong whether it holds up a bridge or stirs your dinner.
Some materials come from nature: wood from trees, wool from sheep, cotton from plants, and rock and metal from the ground. Others are made by people, like most plastics. Either way, understanding what materials are made of links closely to Atoms and Molecules, the tiny building blocks that give every material its properties.
Changing a material's shape — without changing the material
You can bend a paperclip, squash clay, stretch an elastic band or fold paper. The shape changes, but it is still the same material. This is one kind of change you will meet again when you learn about Reversible and Irreversible Changes. Bending a paperclip is reversible — you can bend it back.
Try this — a material sorting hunt
With a grown-up, gather ten safe objects from around your home, such as a wooden spoon, a plastic cup, a metal key, a cotton sock and a glass jar. Sort them into groups: first by what material they are made of, then by a property — try sorting them into "waterproof" and "absorbent" by dripping one drop of water on each (with permission, and not on anything precious). Which materials let the water soak in, and which made it run off? Write down what you find. You have just done what real material scientists do every day — testing materials to learn their properties.
Once you start noticing materials and their properties, you will understand why everything around you is made the way it is.
Quick quiz
Test yourself and earn XP
What does the word 'material' mean in science?
A material is the substance or 'stuff' an object is made from, such as wood, metal or plastic.
Why is glass a good material for windows?
Glass is transparent (see-through), so it lets light into a room while keeping wind and rain out.
Which property is most important for a raincoat?
A raincoat must be waterproof so the water runs off instead of soaking through to keep you dry.
Why is rubber used for car tyres?
Rubber is flexible and grippy, which helps tyres bend over bumps and hold the road.
Which of these is the BEST reason to choose a material?
Engineers pick a material because its properties suit the job — strong for bridges, soft for pillows.
FAQ
Yes, and most are! A pencil has wood on the outside, graphite in the middle, metal and rubber at the end for the eraser, and paint on the surface. A bicycle uses metal for the frame, rubber for the tyres, and plastic or foam for the seat. Designers combine materials so each part has the right property for its job.
An object is a whole thing you can use, like a spoon, a chair or a bottle. A material is the stuff it is made from, like metal, wood or glass. The same object can be made from different materials — a spoon can be metal, wooden or plastic — and one material can make many different objects.
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