Changing materials
This Topic is About...
- I will find out which materials can stretch, squash, twist, or bend.
- I will measure how far rubber bands can stretch.
- I will make predictions and check if I was right.
You’re ready to test materials and make smart predictions!
Key Words
- bent
- elastic
- measure
- shapes
- compressed
- stretched
- twisted
Tap to Learn the Meanings!
- bent: Changed shape by being curved or folded.
- elastic: Can stretch and then go back to its original shape.
- measure: To find out how long, how heavy, or how big something is.
- shapes: The outlines or forms of objects, like circles or squares.
- compressed: Squashed or pressed into a smaller space.
- stretched: Pulled longer or wider than before.
- twisted: Turned around and around in opposite directions.
Great job learning new science words!
Shapes of Objects
The football is round.

Flat and Different Shapes
The paper is flat. They have different shapes.
Changing the Shape of Materials
We can change the shape of most materials.

Ways to Change Shape
Most materials can be squashed, compressed, twisted or bent.

What Does “Elastic” Mean?
Materials that stretch and then go back to their old shape are called elastic.
Rubber is Elastic
Rubber is an elastic material.
Elastic Rope
The rubber rope keeping this woman safe is elastic.
Think Like a Scientist
Which rubber band stretches most?
You will need: some rubber bands, small bricks, a paperclip, string, a pot or small bag, some stones or marbles, a stick or wooden ruler, two chairs.
Investigate this question:
Which rubber band stretches most?
What to do:
- Look at the pictures to see what to do.
- Predict which rubber band will stretch most.
- Count the bricks to measure how far different rubber bands stretch.

How am I doing?
Check your friend’s measuring.
Have they counted the right number of bricks?
Which rubber band stretched the most?
Was your prediction right?