Grade 3 Science Revision Unit 5

Materials and Their Properties

• Properties describe the characteristics of materials, e.g., strength, rigidity, absorbency.
• Metals are generally strong materials, while rubber is known for being waterproof or absorbent.
• Rigid materials, like bricks, maintain shape and resist bending, unlike flexible materials.
• Common types of materials:
  • Fabric: usually absorbent, not typically waterproof.
  • Ice: can be considered dull in texture and easily breakable.
  • Wood: has a dull appearance and is also flexible.

Magnets and Magnetic Properties

• Magnetic materials are attracted to magnets (e.g., iron), while non-magnetic materials are not.
• Glass is classified as non-magnetic, while iron is a magnetic material.

Material Sorting

• Materials can be sorted based on their characteristics:
  • Strength: strong (e.g., steel) vs. weak (e.g., paper)
  • Flexibility: flexible (e.g., rubber) vs. rigid (e.g., a table)
  • Absorbency: absorbent (e.g., fabric) vs. waterproof (e.g., plastic).

Sensibility of Material Usage

• Some material combinations are deemed sensible, and others silly:
  • Rubber bikes or fabric tables are considered silly since those materials do not suit their functions.
  • A window made of glass is sensible while a knife made of ice is silly.

Summary of Sorting Methods

• Sorting can be based on appearance, texture, and functional characteristics of materials.
• Examples of sorting criteria include whether a material is transparent, shiny, strong, or absorbs liquids.

Reminder

• Understand various materials and their common properties to aid in recognizing their appropriate use and sorting characteristics effectively.