This World of Things

Given: Khushi drew a picture of her bright classroom with sunlight shining through the windows.

Answer (sample names of things typically seen in a classroom):
- Window (with glass panes)
- Door (with hinges and latch)
- Table
- Chair
- Blackboard / Chalkboard
- Light bulb
- Electric switch
- Mat / Floor

*(Note: Students should label the objects they can identify in the picture provided in their textbook.)*

Given: A classroom window with a glass pane.

Concept: Materials that allow light to pass through them completely are called transparent materials.

Answer: Yes, we can see through the window glass because glass is a transparent material. It allows light to pass through it freely, so we can clearly see objects on the other side — like trees, flowers, and the sky outside.

Instructions for students:
1. Observe your classroom carefully.
2. Draw the classroom showing objects such as: desks, chairs, blackboard, windows, doors, light bulbs, electric switches, mats, fans, etc.
3. Label each object clearly.

Sample labels to include:
- Table (made of wood)
- Chair (made of wood)
- Window (made of glass and wood/metal frame)
- Door (made of wood, with metal hinges and latch)
- Light bulb (made of glass)
- Electric switch (made of plastic)
- Mat (made of fibre/cloth)

*(This is a hands-on activity; students should draw and label based on their own classroom.)*

Given: We need to find objects made of metals in and around the classroom.

Concept: Metals are materials that are usually shiny, hard, and conduct heat and electricity. Common metals include iron, copper, aluminium, gold, silver, and alloys like steel, brass, and bronze.

Sample list of metallic objects and the metals they are made of:

| Object | Metal |
|---|---|
| Door hinges | Iron / Steel |
| Nails | Iron / Steel |
| Door latch | Iron / Steel |
| Spoon | Steel / Stainless steel |
| Coins | Copper / Nickel alloy |
| Tap / Faucet | Brass |
| Aluminium foil | Aluminium |
| Wires inside bulb | Tungsten / Copper |
| Bangles | Gold / Silver / Brass |

*(Students should add objects they observe around them.)*

Answer:
- Mats — made of fibre, coir, or cloth (natural or synthetic material)
- Light bulbs — made of glass (the outer covering) and metal (the base and filament inside)
- Electric switches — made of plastic (the outer casing) and metal (the internal contacts/wires)

So different objects in the classroom are made of different materials such as wood, metal, glass, plastic, and fibre.

Answer (sample):
- Yes, my window has a glass pane.
- Yes, I can see through it clearly because glass is transparent.
- Through the window I can see: trees, flowers, the sky, birds, other buildings, and people walking outside.

*(Students should write what they actually see through their own classroom or home window.)*

Given: We observe different materials to check how much light passes through them.

Concept:
- Transparent — allows light to pass through completely; objects can be seen clearly.
- Translucent — allows light to pass through partially; objects appear blurry.
- Opaque — does not allow light to pass through; objects cannot be seen.

Sample completed table:

| See through clearly (Transparent) | See through partially (Translucent) | Cannot see through at all (Opaque) |
|---|---|---|
| Clear glass bottle | Butter paper | Metal utensil (steel bowl) |
| Clear plastic bottle | Thin white cloth | Thick cardboard |
| Plain glass | Frosted glass | Wooden plank |
| Water in a glass | Tissue paper | Thick plastic bag |

*(Students should fill in based on their own observations.)*

Answer: One more material that is transparent is clear/plain water.

Other examples of transparent materials:
- Clear plastic (like a transparent plastic bag or bottle)
- Air

Explanation: These materials allow light to pass through them completely, so we can see objects clearly through them.

Given: Translucent materials allow light to pass through only partially — we can see through them, but not clearly.

Examples of translucent materials:
1. Butter paper (used in baking)
2. Frosted glass (used in bathroom windows)
3. Thin white cloth or muslin
4. Tissue paper
5. Wax paper
6. Some types of plastic sheets

Explanation: When you hold butter paper or frosted glass in front of a light source, you can see the light but cannot see the objects clearly behind it.

Given: We look at objects through coloured transparent materials.

Concept: When light passes through a coloured transparent material, only that colour of light passes through, making everything appear in that colour.

(a) Does the colour of the paper appear to change?
Yes! The white paper appears to take on the colour of the transparent material we are looking through. For example, through blue plastic, the white paper looks blue.

(b) Does white paper appear different through thin blue or yellow plastic/glass?
Yes:
- Through blue plastic → white paper looks blue
- Through yellow plastic → white paper looks yellow

(c) Do the colours of different objects appear to change?
Yes, the colours change. For example:
- A blue object seen through yellow plastic appears green (because blue + yellow = green in light mixing).
- A red object seen through blue plastic appears dark/purple.

(d) Earlier experiences:
Yes — for example, looking through coloured sunglasses, looking through the coloured glass of a stained-glass window, or looking through a coloured cellophane wrapper all give similar experiences.

*(Students should record their own observations from the activity.)*

Given: A table with materials and example objects.

Completed table (sample answers):

| Khushi's list | Name of the material | Objects made of this material in your classroom or home |
|---|---|---|
| Table, chair, door | Wood | Pencil, bookshelf, window frame, cricket bat, ruler |
| Door hinges, nails | Metal | Spoon, scissors, needle, coin, tap, lock |
| Windowpanes, light bulb | Glass | Mirror, spectacles, glass tumbler, bottle |
| Electric switches | Plastic | Pen, comb, bucket, water bottle, toy |
| (Additional row) | Clay | Pot, earthen lamp (diya), flower vase |

Sources of materials:
- Wood → Trees (forests)
- Metals → Earth / Mines (metals are extracted from ores found underground)
- Cloth → Plants (cotton comes from the cotton plant) and Animals (wool comes from sheep; silk from silkworms)

Answer:

- Wood → Trees (forests)
- Metals → Earth / Underground mines (metals are found as ores in the earth's crust and are extracted by mining)
- Cloth → Plants and Animals
- Cotton cloth → Cotton plant
- Woollen cloth → Sheep (wool)
- Silk cloth → Silkworm
- Jute cloth → Jute plant

Conclusion: Most materials we use come from nature — either from plants, animals, or from the earth.

This is a discussion/interview activity. Sample answers based on common knowledge:

(a) Were things made of the same materials in their childhood?
Not always. For example:
- Buckets and containers were often made of metal (iron or brass), whereas today we mostly use plastic buckets.
- Combs were made of wood or bone, now they are mostly plastic.
- Toys were made of wood or clay, now many are made of plastic.

(b) Are there new materials now that they might not have seen before?
Yes! Plastic is a relatively new material that was not widely used in earlier times. Synthetic fibres (like nylon and polyester) for clothes are also newer materials.

(c) Are there materials from their childhood not in use now?
Yes, for example:
- Clay pots for storing water were very common but are now replaced by plastic or metal containers.
- Leaf plates (pattal) were used for eating but are now replaced by plastic or steel plates.
- These older materials are less used because newer materials are cheaper, lighter, or more durable.

*(Students should record actual answers from their grandparents.)*

Given: We observe and describe a spoon.

Answer (for a typical steel/metal spoon):
- Material: The spoon is made of metal (stainless steel).
- Description:
- ✅ Smooth — the surface of a metal spoon is smooth.
- ✅ Shiny — metal spoons are shiny and reflect light.
- ✅ Feels cold to the touch — metals feel cold when you first touch them because they conduct heat away from your hand quickly.
- ❌ Not rough.
- ❌ Not dull (it is shiny).

For a wooden spoon:
- Smooth or slightly rough, Dull (not shiny), does NOT feel cold to the touch.

*(Students should describe the spoon they actually have at home.)*

Given: We tap a metal spoon on objects of different materials and observe the sounds.

Concept: Different materials produce different sounds when struck because of their different densities and structures.

Sample observations:

| Object / Material | Sound produced | Description in words |
|---|---|---|
| Metal (steel bowl) | Ting-ting | Clear, ringing, sharp |
| Wood (wooden table) | Thak-thak | Dull, heavy, flat |
| Plastic (plastic bottle) | Tak-tak | Light, hollow |
| Cloth (bag) | Dub-dub | Soft, muffled |
| Glass (glass tumbler) | Ting-ting (high pitch) | Clear, musical, sharp |

Sample beat composition:
Ting, Ting, Thak, Thak
Ting, Thak, Ting, Thak!
Tak, Tak, Dub, Ting!

*(Students should compose their own beats based on their observations.)*

Answer:

Other materials used to make tables:
- Metal (iron or steel)
- Plastic
- Glass (glass-top tables)
- Stone or marble

Can we use fabric or rubber to make a table?
No, we cannot use fabric or rubber to make a table.

Reason:
- Fabric is soft and flexible — it cannot hold its shape or support weight. A table made of fabric would collapse.
- Rubber is also flexible and elastic — it would bend and not provide a firm, flat surface to keep things on.

Conclusion: A table needs to be made of a hard and rigid material so that it keeps its shape and can support the weight of objects placed on it. Wood, metal, and stone are hard and rigid, making them suitable for making tables.

Given: We must find unsuitable material-object pairs and explain why.

Concept: The material used to make an object must match the properties needed — hardness, flexibility, waterproofing, strength, etc.

Completed table:

| S. No. | Object | Unsuitable Material | Reason |
|---|---|---|---|
| 1. | Umbrella | Paper | Paper will tear if it gets wet in the rain |
| 2. | Chair | Cloth | Cloth is soft and flexible; it cannot hold a person's weight and will not keep its shape |
| 3. | Cooking pot | Plastic | Plastic melts when heated on a stove; it cannot withstand high temperatures |
| 4. | Window pane | Wood | Wood is opaque; we cannot see through it, so it would block light and the view |
| 5. | Shoes | Glass | Glass is hard and brittle; it would break easily and hurt the feet |
| 6. | Walls | Water | Water is a liquid; it flows and cannot hold a fixed shape, so walls made of water would collapse immediately |

Given: Objects — ink, a stone, smoke, ice, steam, a spoon, honey, a bottle, a bag, water.

Concept:
- Solid — has a fixed shape and does not flow (e.g., stone, wood).
- Liquid — has no fixed shape; it flows and takes the shape of its container (e.g., water, milk).
- Gas — has no fixed shape or volume; it spreads out in all directions (e.g., air, steam).

Grouping:

🟫 Tray (Solids):
- A stone
- Ice
- A spoon
- A bottle
- A bag

🔵 Bottle (Liquids):
- Ink
- Honey
- Water

🎈 Balloon (Gases):
- Smoke
- Steam

Confusing objects (neither clearly solid, liquid, nor gas):
1. Sand — looks like it flows (like a liquid) but each grain is actually a tiny solid.
2. Sponge — is a solid but has holes filled with air; it can absorb liquids.
3. Clay — is a solid but can be moulded and shaped like a liquid when wet.

*(Students can add their own examples to the tray, bottle, and balloon.)*

Given: Natural things exist in nature (not made by humans). Artificial things are made by people.

Concept:
- Natural things may be living (plants, animals) or non-living (rocks, water, air).
- Artificial things are manufactured or created by human beings.

Answer:

Natural things (5 examples):
1. Mango tree
2. River / Water
3. Rocks / Stones
4. Birds
5. Air / Wind

Artificial things (5 examples):
1. Table
2. Shoes
3. Plastic bottle
4. Electric bulb
5. Clothes / Fabric

Given: Khushi drew a mango tree with mangoes growing on it.

Answer: Khushi most likely drew her picture around June (summer season).

Reason: Mango trees bear fruit during the summer months — typically from April to July in India. Mangoes are ripe and available in the market during this time. In January, it is winter and mango trees do not bear fruit — they may not even have flowers yet.

Conclusion: Since Khushi drew a mango tree with mangoes on it, the picture was drawn around June (summer), not January.

Answer:

Three materials we commonly see around us are:

1. Wood — used to make furniture like tables, chairs, and doors.
2. Metal (e.g., iron/steel) — used to make nails, hinges, spoons, and utensils.
3. Plastic — used to make bottles, bags, switches, and pens.

*(Other acceptable answers: glass, cloth/fabric, clay, rubber, stone.)*

Given: A shining spoon — we need to find out if it is truly metal or just painted to look shiny.

We can test it in the following ways:

1. Feel the temperature: Hold the spoon for a moment. If it feels cold to the touch and quickly takes on the temperature of your hand, it is likely metal (metals are good conductors of heat). Non-metals like plastic or wood do not feel as cold.

2. Tap it: Gently tap the spoon on a hard surface. A metal spoon produces a clear ringing sound (ting-ting). A plastic or wooden spoon produces a dull sound.

3. Check the weight: Metal spoons are generally heavier than plastic or wooden spoons of the same size.

4. Scratch test: Gently scratch a hidden part of the spoon. If the scratch reveals a different colour underneath, it may be painted. If the colour is the same throughout, it is likely the natural material.

5. Magnet test: If you have a magnet, bring it near the spoon. If the spoon is attracted to the magnet, it is made of iron or steel (a metal).

Conclusion: By using these simple tests — feeling the temperature, tapping, checking weight, scratching, and using a magnet — we can find out whether the spoon is truly made of metal or just painted to look shiny.

Instructions for students:

Three Natural things to draw:
1. A tree (e.g., mango tree with fruits)
2. A river or a pond with water
3. A bird (e.g., sparrow or parrot)

Three Artificial things to draw:
1. A table and chair
2. A plastic bottle
3. An electric bulb

Remember:
- Natural things are found in nature and are NOT made by humans.
- Artificial things are made by humans.

*(Students should draw these in their notebooks with neat labels.)*

Given: We need to match the type of material with the correct example.

Concept:
- Transparent — allows light to pass through completely; we can see clearly through it.
- Translucent — allows light to pass through partially; we can see only partially through it.
- Opaque — does not allow light to pass through; we cannot see through it.

Correct Matches:

| Type | Object |
|---|---|
| Transparent | A glass used in spectacles |
| Translucent | A lamp shade made of paper |
| Opaque | A plate |

Explanation:
- Spectacle glass is transparent — we can see clearly through it.
- A paper lamp shade is translucent — it allows some light to pass through but we cannot see objects clearly through it; it glows softly.
- A plate (made of metal, ceramic, or thick plastic) is opaque — no light passes through it.