Grade 3 · Unit 5: Investigating materials

Uses of materials

Why is a saucepan made of metal with a plastic handle?

Each part of a bicycle is made from a material that suits its job.

The right material

We choose materials that are suitable for the job. We think about their properties. A window must be transparent. A chair must be strong and rigid.

In the kitchen

Saucepans are made of metal because metal is a good conductor of heat. Heat passes through the metal to cook the food. The handle is plastic or wood because these are insulators. They stay cool to hold.

Building

Buildings and bridges need strong, durable materials. Bricks, concrete and steel are used because they are strong and last a long time. In villages, bamboo is used for houses and bridges because it is strong and light.

Bags and clothes

Jute and cloth bags are strong and can be used again and again. Raincoats are made of waterproof materials. Summer clothes are made of cotton because it is light and absorbs sweat.

Choosing materials also means thinking about the environment. Plastic bags are cheap but can last hundreds of years as litter.

What I learnt