Air And Water

Air is the invisible mixture of gases that surrounds the Earth. We cannot see air, but we can feel and use it. Air is all around us — inside rooms, outside, above the ground and between the trees.

Important things about air:

• Air is invisible but it takes up space. You can show this by blowing up a balloon — the balloon gets bigger because air fills it.
• Air has weight. Even though we cannot see it, air pushes on things. For example, a closed bottle feels heavier with air inside than if it were empty of air (experiment with a balloon or syringe shows this idea).
• Air can move. Moving air is called wind. Wind can cool us, move leaves, fly kites and help windmills work.
• Air is made of tiny particles (very small bits). These particles are spread out so air is lighter than water or solids.
• Air is important for life. People, animals and plants need air (oxygen) to live. Air also helps fire burn and sound to travel.

Simple experiments children can do: blow up balloons, place a glass upside down in water to see air trapped inside, feel the wind with a hand or make a paper windmill.

What is air?
Air is a mixture of gases that surrounds the Earth. We cannot always see air, but it is everywhere — around us, inside balloons, inside tyres and bottles.

Main properties of air

• Air takes up space: Air fills any container it is put into. When you blow up a balloon the balloon gets bigger because air fills its inside.
• Air has weight: Even though we cannot see it, air has weight. A balloon filled with air weighs a little more than the same empty balloon.
• Air has pressure: Air pushes on everything around it. This push is called air pressure. We feel air pressure when wind pushes against our faces or when a pump forces air into a tyre.
• Air can be compressed and expanded: Air can be made smaller (compressed) by pushing it into a small space (like using a pump) and it can expand to fill a bigger space.
• Air is invisible, usually odorless and tasteless: We usually cannot see air. Sometimes smell or dust makes the air noticeable.
• Air moves (wind): Moving air is called wind. Wind can move leaves, kites and small objects.
• Air supports life and burning: Air contains oxygen which animals and humans need to breathe and which helps fire burn. Plants need carbon dioxide (also a part of air) to make food.
• Air is a mixture of gases: The main gases are nitrogen and oxygen with small amounts of other gases.

Simple classroom activities to show these properties

• Put a glass upside down in a water tray and press it down: trapped bubbles show air takes up space.
• Weigh a deflated balloon and then an inflated balloon to show air has weight (use a simple balance or kitchen scale).
• Cover a burning candle with a jar: the flame goes out after some time because the air inside the jar changes (shows air is needed for burning).
• Use a bicycle pump to inflate a tyre or ball — you can feel the resistance as air is pushed in (shows air can be compressed).

Composition of air (simple)
Air is mostly nitrogen and oxygen. A simple split is: about 78% nitrogen, 21% oxygen and 1% other gases (argon, carbon dioxide, etc.).

Why air is important
Air gives us oxygen to breathe, helps plants make food, helps move weather and clouds, and lets birds and planes fly.

Air is the invisible mixture of gases all around us. We breathe it, plants use parts of it, and it helps weather happen.

Main components of air (approximate amounts):

• Nitrogen (~78%) — the largest part. It is mostly harmless and does not burn.
• Oxygen (~21%) — what animals and humans need to breathe; it also helps burning.
• Argon (~0.93%) — a small, inactive gas that stays quiet in the air.
• Carbon dioxide (~0.04%) — used by plants to make food (photosynthesis).
• Water vapour and tiny particles — makes the air damp or causes fog, and small dust, smoke, or pollen particles make air dirty sometimes.

These amounts are simple averages for clean air. Near busy roads, factories, or fields the small parts (like smoke, dust or extra carbon dioxide) can be higher.

Why each part matters (simple):

• Nitrogen keeps the air stable.
• Oxygen lets us and animals live and helps fires burn.
• Carbon dioxide helps plants grow.
• Water vapour makes rain, clouds and humidity.

Air is all around us. We cannot see air but we can feel it when it blows as wind. Air is very useful in many ways in our daily life. Some important uses of air are:

• Breathing: People and animals breathe air to get oxygen which helps them live.
• Helps plants: Plants take carbon dioxide from air to make their food and air helps carry pollen and seeds to make new plants.
• Makes things move: Moving air (wind) helps kites fly, moves leaves, and fills the sails of boats so they can travel.
• Inflating: Air fills balloons, tyres, footballs and other items so they keep their shape and work well.
• Cools us: A breeze or fan blows air that cools our body on a hot day.
• Helps burning: Oxygen in air helps fire burn when we cook or light a candle (always be careful with fire).
• Helps sound travel: Sound moves through air, so we can hear people talking and birds singing.

Air is a mixture of gases. The main parts are nitrogen and oxygen. This is why air is useful for many different things.

What is wind?
Wind is moving air. When air moves from one place to another, we feel it as wind.

How is wind made?
The Sun heats the Earth unevenly. Warm air becomes lighter and rises. Cooler air moves in to take its place. This movement of air from cool places to warm places is wind.

Kinds of wind (simple)
- Breeze: a gentle wind you can feel on your face.
- Strong wind/gale: a very fast wind that can move branches and umbrellas.
- Gust: a short, sudden burst of stronger wind.

How we notice and measure wind
We notice wind when it moves leaves, hair, flags, or kites. Tools to measure wind include a wind vane (shows direction) and an anemometer (measures speed).

Simple activities to see wind
- Make a pinwheel or paper windmill and watch it spin.
- Hold a scarf to see which way the wind blows.
- Use a light object (paper, leaf) and see how far it moves in a few seconds.

Why wind is important
Wind helps dry wet clothes, moves clouds and weather, helps boats sail, and makes windmills or wind turbines produce electricity. But very strong wind can be dangerous, so we stay safe indoors during storms.

What is air? Air is the invisible mix of gases all around us. We need it to breathe, to help plants grow, and to keep us healthy.

What is air pollution? Air pollution happens when smoke, dust or harmful gases get into the air and make it dirty. Dirty air is called polluted air.

Causes of air pollution

• Smoke from vehicles (cars, buses, trucks).
• Smoke and gases from factories and chimneys.
• Burning of leaves, trash or wood.
• Dust from construction sites and roads.

How polluted air affects us

• People can cough, have a sore throat or find it hard to breathe.
• Plants and animals may not grow well.
• Sky can become grey and dusty.

Ways to keep air clean

• Plant trees and care for plants — trees make clean air.
• Use dustbins and do not burn rubbish or leaves.
• Walk, cycle or use public transport instead of using many cars.
• Turn off engines when not moving and use cleaner fuels when possible.
• Cover factories and cook stoves with chimneys that go high and filter smoke.

How can children help? Plant a small tree, remind family not to burn trash, walk or cycle to nearby places, and keep classrooms and home clean.

What is water?

Water is a liquid that we drink and use every day. It is found in rivers, lakes, ponds, wells, and the sea. Water is also in the air as tiny invisible drops called vapour and as ice when it becomes very cold.

Properties of water (simple):

• Colourless, tasteless and mostly odourless.
• Can be a liquid (water), a solid (ice) and a gas (steam or vapour).
• Freezes at 0°C and boils at 100°C (at sea level).

Why is water important?

• We need water to drink and stay healthy.
• Plants and animals need water to live.
• We use water for cooking, bathing, cleaning, and growing food.

The simple water cycle (easy words)

1. Evaporation: Sun heats water in rivers, lakes and puddles and turns it into vapour.
2. Condensation: Vapour cools and becomes tiny drops that form clouds.
3. Precipitation: When drops in clouds join together they fall as rain or snow.
4. Collection: Rainwater collects in rivers, lakes and the ground, and the cycle repeats.

How we can save water (simple tips)

• Turn off the tap while brushing teeth.
• Fix leaking taps.
• Use a bucket to wash a vehicle instead of a running hose.
• Water plants in the early morning or evening to avoid quick evaporation.

Short safe-handling note

Always drink clean water. If water is dirty, boil or filter it (ask an adult for help).

What is water used for? Water is very important in our daily life. We need it for many things at home, in farms, in factories and for nature. Here are the main uses of water explained simply for Class 2 students.

• Drinking: All people and animals drink water to stay healthy and alive. We should drink clean water.
• Cooking: We use water to wash vegetables, cook rice and make soup or tea.
• Bathing and Personal Care: We use water for bathing, brushing teeth and washing hands to stay clean.
• Washing Clothes and Utensils: Water is used to wash clothes, plates, and pans.
• Cleaning Home and School: We mop floors, clean tables and toilets with water.
• Watering Plants and Farming: Farmers use water to grow crops and we water plants and gardens at home.
• Animals: Animals need water to drink and stay healthy.
• Firefighting: Firefighters use water to put out fires.
• Transport and Fun: Boats need water to move on rivers and seas; we also use water for swimming and playing in safe places.
• Making Things and Electricity: Factories use water to make products; dams use water to make electricity (hydropower).
• Nature: Rivers, lakes and ponds need water to keep fish and plants alive and to keep the environment healthy.

How to save water: Turn off the tap while brushing, fix leaks, use a bucket for watering plants, and reuse water when you can (for example, water from washing vegetables can water plants).

Safety: Always drink clean water. If water is dirty, it should be boiled or cleaned before drinking.

Clean and safe drinking water is water that is free from dirt, germs and harmful chemicals so it is safe for us to drink. We get water from many places like taps, wells, rivers, lakes and rain. Water from these sources can sometimes have dust, tiny living germs (microbes) or harmful substances that can make people sick.

We can make water safe in simple ways: boil it until it boils well so germs are killed; pass it through a clean cloth or filter to remove dirt; use a little chlorine or water purification tablets when needed; and store water in a clean, covered container so it stays safe. Always wash your hands with soap before touching drinking water or eating.

Keeping water safe also means saving it. Close the tap while brushing teeth, fix leaks and collect rainwater in a clean bucket for later use. Clean water helps us stay healthy, grow food and keep our homes and schools clean.

• How to tell if water is safe: it looks clear, has no bad smell and tastes normal.
• Simple safety steps at home: boiling, filtering, covering containers and using a clean cup or ladle to take water.
• Why it matters: drinking dirty water can cause stomach ache, diarrhea and other illnesses, especially in little children.

What is water pollution?

Water pollution happens when harmful things like dirt, plastic, oil, chemicals or germs get into rivers, lakes, ponds or tap water. Polluted water looks dirty, smells bad and can make people, animals and plants sick.

Where does pollution come from?

• Household waste and plastic thrown into water.
• Sewage and dirty water from homes and streets.
• Factory chemicals or oil spilled into rivers.
• Farming chemicals (pesticides, fertilizers) washed into streams.

How does it harm life?

• Fish and animals may die or get sick.
• People can get stomach illnesses if they drink polluted water.
• Plants that grow in water may not get sunlight and air, so they die.

How can we prevent water pollution?

• Do not throw plastic, bottles or trash into water bodies. Use dustbins.
• Never pour oil, paints or chemicals into drains.
• Fix leaky taps and save water so less dirty water is made.
• Plant trees and plants near water to stop soil washing into rivers.
• Schools and families can organise clean-up drives for ponds and rivers.
• Treat water before sending it back to rivers (sewage treatment) — this is done by adults and governments.

Simple activities for children

• Make a small water filter using cloth, sand and charcoal to see how dirty water becomes clearer.
• Collect trash from a nearby safe place (with adult help) and count plastic bottles to learn how much plastic is thrown away.

Safety note: Never drink water from rivers or ponds without an adult and proper treatment.

What is Water Conservation?

Water conservation means using water carefully so that we do not waste it. Water is precious because plants, animals and people need it to live. There is only a little fresh water on Earth that we can use, so we must save it.

Why should we save water?

• To make sure there is enough water for drinking, bathing, farming and growing food.
• To help plants and animals survive.
• To save energy and money (treating and pumping water costs energy).

How can we save water? (Easy actions for Class 2 students)

• Turn off the tap while brushing your teeth or soaping your hands.
• Take shorter baths or showers.
• Use a bucket and mug to bathe instead of filling a big tub.
• Fix leaking taps or tell an adult to repair them.
• Use a small bowl to wash vegetables and reuse that water to water plants.
• Collect rainwater in a small container and use it for plants.
• Share water-saving tips with family and friends.

Small activity to understand saving: Place a 1-litre bottle under a running tap for 1 minute to see how much water flows. Then brush teeth with the tap off to see how much you can save.

Benefits of saving water:

• Helps life to grow and stay healthy.
• Leaves more water for everyone.
• Protects rivers, lakes and animals.

What is interdependence? Interdependence means living things need other living things and things in nature to live. Air and water are two very important things that all living things depend on.

Why do living things need air? Air has oxygen. Animals and humans breathe in oxygen to get energy. Plants take in carbon dioxide (a part of air) to make food and they give out oxygen. Some animals like fish get oxygen from water using gills.

Why do living things need water? Water helps plants take nutrients from the soil and is used to make food. Animals and humans drink water to stay healthy, grow, and to help their bodies work. Seeds need water to sprout.

How they help each other: Plants use water, carbon dioxide and sunlight to make food and release oxygen. Animals and humans breathe oxygen and eat plants (or animals that ate plants). This exchange shows how air, water, plants and animals depend on one another.

Important idea for Class 2: If we keep air clean and save water, all living things will stay healthy.

Simple activities and experiments help young learners see what air and water do around us. They are safe, short, and use common household things. Each activity shows one idea: that air takes up space and is all around us, that water can change (evaporate and condense), and that some things float while others sink. Doing, watching and asking “why?” helps children learn by doing.

Activity 1: Air takes up space

Materials: an empty plastic bottle and a balloon.

Steps: Put the balloon’s mouth over the bottle neck. Try to blow the balloon up while it is in the bottle.

Observation: The balloon does not inflate fully because the bottle already has air inside.

What it shows: Air is present inside the bottle and takes up space. If you remove some air (e.g., by tilting the bottle and letting air out) the balloon can inflate more.

Activity 2: Air is in water (bubbles)

Materials: a glass of water and a straw or a spoon.

Steps: Stir the water or blow gently through the straw into the water.

Observation: Bubbles form and rise to the surface.

What it shows: Air mixes with water as bubbles. Water may look clear but contains air too.

Activity 3: Mini water cycle (evaporation and condensation)

Materials: a wide bowl, a small cup, water, cling film (plastic wrap), a small stone.

Steps: Put the small cup in the center of the bowl. Pour water into the bowl so the water level is below the cup rim. Cover the bowl with cling film and put a small stone in the middle so the film dips slightly over the cup. Place the bowl in sunlight and wait a few hours.

Observation: Water droplets form on the cling film and drip into the cup.

What it shows: Water evaporates (turns into vapor), then cools and becomes droplets (condensation) and falls into the cup (precipitation). This models rain and the water cycle.

Activity 4: Floating and sinking

Materials: a bowl of water, a coin, a small plastic toy, a small paper boat or leaf.

Steps: Gently place each object on the water and watch whether it floats or sinks.

Observation: Some objects float (paper boat, plastic toy), others sink (coin).

What it shows: Whether something floats depends on its material and shape. Objects that are lighter for their size or shaped to push water away can float.

Activity 5: Evaporation test

Materials: two shallow dishes and water, a sunny spot and a shaded spot.

Steps: Put equal amounts of water in both dishes. Place one in the sun and one in the shade. Check after several hours or a day.

Observation: The dish in the sun will lose more water (less water left) than the one in the shade.

What it shows: Heat from the sun makes water evaporate faster. Evaporation turns liquid water into invisible water vapour.

Safety tips: Do not use fire without adult help. Use adult supervision for all activities. Use safe, non-toxic household items.

Conclusion: Simple experiments help children observe that air is everywhere and takes space, water can change between liquid and vapor and fall as rain, and different objects behave differently in water (float or sink). These ideas form the basis for understanding weather, breathing, and why boats float.

What is safety and hygiene?
Safety means keeping ourselves safe from harm. Hygiene means keeping our body, home and surroundings clean so we do not get sick.

Why clean air and water are important
Air and water help us live. Clean air keeps our lungs healthy. Clean water keeps our body working and helps us stay strong. Dirty air and water can make us cough, get fever, or have stomach problems.

How air becomes dirty (air pollution)

• Smoke from vehicles, factories and burning rubbish.
• Dust from roads and construction.
• Bad smell from dirty drains and garbage.

How water becomes dirty (water pollution)

• Throwing garbage or chemicals into rivers, ponds and lakes.
• Dirty water from homes or factories mixing with clean water.
• Open drains and toilets near water sources.

Simple safety and hygiene rules (home and school)

• Wash hands with soap and water before eating and after using the toilet.
• Cover your mouth and nose with a cloth or elbow when coughing or sneezing.
• Do not spit or throw garbage on the road; use dustbins.
• Drink only clean water — water that is boiled, filtered or from a safe tap.
• Keep water containers covered so dust and insects do not get in.
• Do not burn plastic or leaves in the open; it makes the air dirty.
• Plant trees and keep the surroundings clean to get fresh air.

What to do if water looks dirty
If water is cloudy or smells bad, do not drink it. Ask an adult to filter or boil it first. For safety, boiling until it bubbles and letting it boil for about one minute makes it safer to drink.

How everyone helps
Children can help by washing hands, keeping bottles covered, throwing waste in dustbins and reminding family members to keep the house and surroundings clean. Schools can teach these habits and provide clean drinking water.

Result of good habits
When we follow safety and hygiene rules, fewer people fall sick. We breathe easier and drink safe water. Our community becomes healthier.