Primary 4 · Science · Chemical sciences
Natural and processed materials
Students compare natural materials such as wood, wool and stone with processed materials such as paper, plastic and glass, and link their properties to their uses.
Awaiting educator review. This material was drafted by our content team with AI assistance and is waiting for review by a qualified educator. Please check it suits your child before using it. Created 10 October 2026. How we review
These lessons were written around Australian Curriculum strands and matched to Singapore levels by age (Primary 1 is the first year of primary school). They are not aligned to MOE syllabuses or the PSLE, so check them against the syllabus your child is working towards.
Learning goals
Learners will
- Distinguish between natural materials and processed materials.
- Describe properties of materials, such as strong, flexible, waterproof, transparent and absorbent.
- Explain why a material is chosen for a particular use because of its properties.
Success looks like
- I can sort materials into natural and processed and explain my choice.
- I can test and describe a material's properties.
- I can explain why an object is made from a certain material.
The big idea
Everything is made of materials. Natural materials come from plants, animals or the ground and are used with little change. They might be cut, cleaned or shaped, but they are still the same material.
- Wood comes from trees, wool from sheep, cotton from cotton plants and stone from the ground.
Processed materials are made when people change natural materials into a new material using heat, water, chemicals or machines.
- Paper is made by breaking wood into tiny fibres, mixing them with water and pressing them flat.
- Plastic is made mainly from oil and natural gas.
- Glass is made by melting sand with other materials at a very high temperature.
Every material has properties. Some properties are: hard or soft, strong or weak, flexible (bendy) or stiff, waterproof or absorbent, transparent or opaque, heavy or light.
We choose materials because of their properties. Glass is transparent, so it is used for windows. Plastic is light and waterproof, so it is used for raincoats and bottles. Wool is soft and warm, so it is used for jumpers. Stone is hard and long-lasting, so it is used for walls and steps. Wood is strong and easy to cut, so it is used for furniture.
Processed materials can have properties that natural materials do not. Glass lets light through like air but keeps out wind and rain. That is why people invented them.
Worked examples
Natural or processed?
Sort: wool, glass, stone, paper, cotton, plastic.
- Ask: is it found in nature and used with little change?
- Wool, stone and cotton are: natural.
- Glass (from sand), paper (from wood) and plastic (from oil) have been changed into new materials: processed.
Answer: Natural: wool, stone, cotton. Processed: glass, paper, plastic.
Absorbency test
Which material is most absorbent: paper towel, cotton fabric, plastic bag or foil?
- Cut each into the same-sized square and put them on a tray.
- Drip 5 drops of water onto each one in the same way.
- Wait one minute and look: does the water soak in or sit on top?
- Paper towel soaks up the water fastest; cotton also soaks it up; on plastic and foil the water sits in drops.
Answer: Paper towel is most absorbent. Plastic and foil are waterproof.
Choosing a material
Which material would be best for a drink bottle for a bike ride: paper, glass or plastic?
- Paper is absorbent, so it would go soggy.
- Glass is waterproof but heavy and can break if dropped.
- Plastic is waterproof, light and does not shatter.
Answer: Plastic, because it is waterproof, light and does not break easily.
Practice check
Have a go, then check your answers. Each answer comes with an explanation.
Answer guide for parents
Which is a natural material?
Stone — Stone comes from the ground and is used with little change.
Glass is made mainly from which natural material?
Sand — Glass is made by melting sand with other materials.
Which property makes glass good for windows?
It is transparent — Transparent materials let light through so we can see out.
Why are raincoats often made of plastic?
It is waterproof — Plastic does not let water through.
Paper is a processed material made from…
wood — Paper is made from wood fibres (or recycled paper).
Is wool a natural or processed material?
natural — Wool comes from sheep and is cleaned and spun but is still wool.
A material that soaks up liquid is called a____________.
absorbent — Absorbent materials soak up liquid.
Which processed material, made mainly from oil, is used for many bottles and toys?
plastic — Most plastics are made from oil and natural gas.
Watch out for
- Students may think 'natural' means 'not touched by people'. Natural materials can be cut, cleaned or shaped; they become processed when they are changed into a new material.
- Some students think processed materials are always worse than natural ones. Each material is chosen for its properties.
- Students may think paper is natural because it comes from trees. Wood is changed into a new material, so paper is processed.
Tips for parents
- Go on a materials hunt in the kitchen and ask 'Natural or processed? Why was it made from that?'
- Keep tests fair: same-sized pieces and the same number of water drops.
- Safety: an adult handles glass; use scissors carefully and wipe up spills straight away so no one slips.
Go further
- Design a lunchbox and choose a material for each part, giving a reason based on its properties.
- Test which fabric scraps are most waterproof by holding them over a cup and pouring a spoonful of water on top.
- Make recycled paper with an adult by soaking scrap paper, blending it into pulp and pressing it flat to dry.
About 45 minutes
You'll need
- Samples: a piece of wood, a wool sock or yarn, a stone, a sheet of paper, a plastic bag or lid, a glass jar (handled by an adult)
- A paper towel, a square of cotton fabric, a square of plastic bag and a square of aluminium foil, all the same size
- A cup of water and a teaspoon or dropper
- A tray to work on
Key words
- natural material
- A material found in nature that is used with little change, such as wood, wool, cotton or stone.
- processed material
- A material made by people changing natural materials into something new, such as paper, plastic or glass.
- property
- A feature of a material, such as how hard, bendy or see-through it is.
- waterproof
- Does not let water through.
- transparent
- Lets light through so you can see clearly through it.
- absorbent
- Soaks up liquid.
Still tricky?
For parents
Want an outside view of where your child is at?
Book a free, no-obligation English and maths assessment at a Success Tutoring centre and get a clear starting point.
Book a free assessmentRelated chemical sciences lessons
Build up to it (Primary 3)
Next steps (Primary 5)