Fill in each blank with the correct word from the lesson.

1. Hard materials like _______ and iron keep their shape when you press or hit them.
2. Scientists call these substances '_______'.
3. This is why we use _______ for hammers but rubber for erasers.
4. Because we choose materials for jobs _______d on exactly these properties.
5. Glass windows must be _______.

Choose the best option for each question.

1. Which property does a rubber eraser have?
   a) Hard and shinyb) Soft and flexiblec) Rough and heavyd) Transparent
2. Why is glass used for windows?
   a) It is softb) It is cheapc) It is transparentd) It is rough
3. Which of these is a HARD material?
   a) Cottonb) Spongec) Stoned) Wool

Write T for True or F for False in the brackets.

1. Soft and flexible is one of the key concepts in the lesson on Grouping Materials.
2. Hard and shiny is the main topic of this lesson.
3. It is transparent is one of the key concepts in the lesson on Grouping Materials.
4. It is soft is the main topic of this lesson.

1. In your own words, explain what Grouping Materials means.
2. List two things you learned from this lesson on Grouping Materials.