Which is the hardest?
rock clay ball nylon swim shorts
Every object is made of one or more materials. A material is a type of matter. Wood, glass, metal, and plastic are common materials.
A material has different properties. A material's properties tell you how it looks, feels, tastes, or smells. Some examples of properties are shiny, hard, fragile, and stretchy.
For example, a shiny material reflects a lot of light. A fragile material breaks when you drop it.
Hard is a property. A hard material keeps its shape when you press on it with your finger.
Look at each picture, one at a time. Imagine pushing on the material shown in each picture.
Of the choices, the rock is the hardest. If you squeeze a rock, it will not change shape.