Comparing materials

For grown-ups: this lesson in words

Years 5 and 6 · Science

Comparing materials: I can test and compare materials, and choose the best material for a job with a reason.

1. Every object is made of a material. Hardness is one property of a material: how hard it is to scratch or squash.

   The brick and the metal key are hard. They are difficult to scratch or squash.

   The sponge and the wool sock are soft. They squash easily.

   Picture: Sorting into 2 groups: Hard, Soft. Hard: Brick, Metal key (key). Soft: Sponge, Wool sock (sock).

2. Transparency is another property. A transparent material lets light through, so we can see through it.

   The glass jar and the clear plastic bottle are transparent.

   The wooden block and the metal can are opaque. Light cannot pass through them.

   Picture: Sorting into 2 groups: Transparent, Opaque. Transparent: Glass jar, Clear plastic bottle (plastic bottle). Opaque: Wooden block (piece of wood), Metal can.

3. Your turn: Sam needs a material for a window, so that people can see out. Which material should he choose?

   Choose one:

   • Glass: glass jar
   • Wood: piece of wood
   • Metal: metal can

   Answer

   The answer: Glass

   Glass. It is transparent, so people can see through the window.

Words to know

material:

What an object is made of, such as metal, wood, plastic or glass.

property:

What a material is like or how it behaves, such as hard or transparent.

transparent:

Lets light through, so you can see through it.

soluble:

Dissolves in water, like sugar or salt.

conductor:

A material that lets electricity or heat pass through it easily.

insulator:

A material that does not let electricity or heat pass through easily.