Materials Around Us — Objects and Properties (1 of 3) · Learner pages

Lesson 1 · Distinguish objects from their materials

Identify an object, its parts and the materials used to make those parts.

Name or initials: ____________   Date: ____________

An object is a thing we use or observe. A material is what a thing is made from. Shape and purpose do not uniquely identify a material.

1. Name the object. Start with the whole item. A pencil is an object; the word pencil does not name the material of every part.
2. Look at its parts. In the illustrated pencil, wood surrounds a graphite core. Record these separately. The illustration shows a model pencil, not every kind of pencil.
3. Allow more than one material. A reusable bottle might have a metal body and a plastic cap. Record which part each material belongs to; do not call the entire bottle plastic because its cap is plastic.
4. Make connections both ways. One material can make several objects, and one kind of object can be made from different materials. Confirm by observation or a label when appearance is uncertain.

Worked example: An observed school bag has cloth panels, a plastic buckle and a metal zip slider. The bag is one object with several parts. A table that says only “bag = cloth” misses the other observed materials.

1. Which word names a material rather than an object?

   1. Wood · 2. Stool · 3. Comb

2. A bottle has a steel body and a plastic cap. Which record is most accurate?

   1. The whole bottle must be steel · 2. The whole bottle must be plastic · 3. Body: steel; cap: plastic

3. Two bowls have the same shape, one steel and one clay. What does this show?

   1. Clay and steel are the same material · 2. One type of object can use different materials · 3. Same shape always means same material

Discuss: Draw one safe intact object. Label two parts and the evidence for each material. Write “not sure” instead of guessing a hidden part.

Explain or demonstrate

Create a part-and-material record for one safe object, including one uncertainty if a part is hidden.

Evidence to include:

• Object named separately from material
• Two part labels linked to materials
• Observation, label or uncertainty stated

Lesson 2 · Classify using a clear rule

Group the same collection in more than one defensible way and connect properties to purpose.

Name or initials: ____________   Date: ____________

Classification is grouping by a stated shared feature. A collection can be regrouped when the question changes.

1. State one rule. The model collection has red and blue wooden cubes, plus red and blue plastic discs. With colour as the rule, each colour group contains more than one material.
2. Change the rule. With shape as the rule, the cubes form one group and the discs another. Moving an item between groups does not change the item.
3. Check every member. With material as the rule, the wooden items belong together and the plastic items belong together. Apply the same rule to every member and explain any uncertain case.
4. Choose a useful classification. The useful rule depends on the task. Colour can help arrange a display; a material property such as water resistance matters when selecting a container. A single property may not be enough.

Worked example: Four cards describe a red cotton strip, a blue cotton strip, a red plastic strip and a blue plastic strip. Grouping by colour makes red/blue groups. Grouping by material makes cotton/plastic groups. Both are valid when the rule is stated.

1. A red wood cube and red plastic disc are grouped together. Which rule fits?

   1. Material · 2. Shape · 3. Colour

2. What should be stated before judging a grouping?

   1. The number of guesses · 2. The grouping rule · 3. The owner’s favourite colour only

3. The same items are regrouped by shape instead of colour. Which statement is true?

   1. Group membership can change without the items changing · 2. The materials must change · 3. Only one grouping can ever be correct

Discuss: Group six safe objects by two different rules. Name each rule, explain one changed membership, and choose which grouping would help find an object quickly.

Explain or demonstrate

Use two rules to sort the same six safe objects. Explain which sorting helps a particular task.

Evidence to include:

• Two explicit criteria
• Membership consistent with each criterion
• A reason tied to the task

Lesson 3 · Compare appearance and softness

Describe surface observations and use hardness or softness as relative properties.

Name or initials: ____________   Date: ____________

Several properties can describe the same material. Shiny, smooth, hard and strong do not all mean the same thing.

1. Observe the surface. Compare samples in the same lighting. Record colour, visible shine and texture as observations. Do not turn a single observation into a complete material identification.
2. Avoid the shine shortcut. Some metals look dull when their surfaces change. Coated plastic can shine. Lustre is useful evidence, but “shiny therefore metal” is not a reliable rule.
3. Compare response to gentle pressure. Use supplied observations or safe soft samples. A sponge changes shape under gentle pressure more easily than a wooden block. Do not scratch furniture, use sharp tools or press a brittle object.
4. Keep the comparison explicit. A rubber sample can be harder to compress than a sponge and easier than a steel block. State what was compared. Hardness is not the same as being unbreakable.

Worked example: In a supplied comparison, sample A is smooth and shiny but bends easily; sample B is dull and rigid. These observations describe surfaces and responses. They do not prove that A is a metal or that B can never break.

1. A shiny plastic folder shows that…

   1. Plastic must always be rough · 2. Some non-metal objects can have shiny surfaces · 3. Every shiny surface is metal

2. Which observation best supports “sample A is softer than B” in a gentle-press test?

   1. A changes shape more easily under comparable pressure · 2. A is blue and B is red · 3. A has a longer name

3. A hard tile breaks when dropped. Which idea is corrected?

   1. All hard materials are soft · 2. Colour decides whether a tile breaks · 3. Hardness does not mean unbreakable

Discuss: Describe two safe samples using at least two properties. State which comparison supports “softer” and one conclusion the observations do not justify.

Explain or demonstrate

Write an evidence-based comparison of a sponge and an eraser using the same gentle-press method. A supplied observation record is acceptable.

Evidence to include:

• Comparable method
• Relative conclusion
• A limit on what the test shows

Final check · Set 1

Try one set after the lessons. Use the other set after reviewing any errors.

1. A wooden toy and a wooden shelf illustrate which idea?

   Every wooden object is a shelf / An object can have no material / One material can make different objects

2. A covered handle looks like metal but has no label. What should you record?

   Definitely silver / Material uncertain; more evidence needed / Definitely iron

3. A container must hold water without leaking. Which property is most relevant?

   Its name must be short / Resistance to water passing through it / Its colour must be red

4. A group labelled “round objects” includes a square tile. What should be checked?

   Whether the tile meets the stated shape rule / Whether the tile is expensive / Whether the label has many letters

5. A dull metal object is observed. What is a sound conclusion?

   A metal surface need not always appear shiny / The object cannot contain metal / All dull objects are wooden

6. Which comparison is stated most clearly?

   Rubber is always the hardest material / Sponge has no material / This rubber sample compresses less easily than this sponge

Final check · Set 2

Try one set after the lessons. Use the other set after reviewing any errors.

1. Which observation supports “this object uses several materials”?

   Its cloth strap is attached to a plastic clip / It has only one colour / It is larger than another object

2. A plastic ruler and a metal ruler both measure length. What is a sound conclusion?

   Measurement requires only plastic / Their units must be different / Objects with a similar purpose can use different materials

3. Two learners sort by colour and by material. How can both defend their work?

   Insist their own rule is the only possible rule / Hide the rule from the other learner / State each rule and check all members against it

4. Why might a shop group similar materials together?

   It changes the mass of the objects / It can help locate and compare items / It makes every item identical

5. Which activity is suitable for this lesson?

   Drop glass to test whether it breaks / Compare a soft sponge and eraser with gentle finger pressure / Scratch a window with a knife

6. A smooth object must also be…

   None of these: softness and mass need separate evidence / Soft / Very light