Green Science 3 Final

d. The plants that live for many years are called ........................
e. Paddy, maize and wheat are called ........................

4. Answer the following questions. 10 × 2 = 20

a. Write any two features of living beings.

b. Why do animals need shelter?

c. Define herbivores with any two examples.

d. Why do animals need food?

e. Define diurnal animals with any two examples.

f. What is meant by hibernation?

g. What are warm-blooded animals?

h. What are shrubs? Give any two examples.

i. Name any four plants from which we get pulses.

j. What are medicinal plants? Give any two examples.

5. Match the following. 5

a. Burrow Goat

b. Sty Dog

c. Stable Rabbit

d. Kennel Horse

e. Pen Pig

6. Identify cold-blooded and warm-blooded animals from the
following. 4

a. b. c. d.

7. Draw a neat picture of lotus plant and colour it. 6

Marks obtained: ...............................................

Student's grade: ...............................................

Teacher's remark: ............................................. Gardian's signature and

Teacher's signature: ......................................... remark

GREEN Science Health and Physical Education Book-3 51

Our Environment unit

7

Weighting Distribution (Approximate)
Teaching periods : 7 Marks (in %): 11

Learning Objectives

After completing the study of this unit, students will be able to:
(i) introduce environment and explain its importance.
(ii) classify wastes into biodegradable and non-

biodegradable.
(iii) introduce pollution and explain types of pollution.
(iv) state the ways to reduce pollution.

Word Power essential degradation
environment non-biodegradable pollution
biodegradable sewage garbage
pollutants smoke decompose
drainage disposal
fertilizers

Teaching Instructions

ó Introduce environment to the students.
ó Explain clean environment and dirty environment.
ó Explain the factors that make the environment dirty.
ó Define biodegradable wastes and non-biodegradable wastes with

examples.
ó Introduce environment pollution to the students.
ó Explain air pollution, water pollution and land pollution.
ó Explain the methods of keeping the environment clean.
ó Evaluate the students asking them various questions related to the

environment and environment pollution.

52 GREEN Science Health and Physical Education Book-3

Environment

Environment is the place where plants and animals live. It is made
of living beings and non-living things. The living beings present in
the environment include different types of plants and animals. The
non-living things present in the environment include air, water,
soil, sunlight, etc.

Air, water, soil, land,

forest, desert, crop

fields, etc. are some

components of the

environment. Our

environment remains

clean if all the

components of the Fig. Fig.

environment remain

clean. The environment 7.1

which is free from Clean environment

waste materials or pollutants is called a clean environment. We

should keep our environment clean to live a healthy life.

Various human activities

make our environment

dirty. Various waste

materials like smoke,

dust particles, sewage,

garbage, plastics, waste

papers, etc. make the

environment dirty. The

environment containing

various waste materials

is called a dirty 7.2 Dirty environment
environment. The waste

materials that make the

environment dirty are called pollutants.

GREEN Science Health and Physical Education Book-3 53

Various types of germs and insects grow and reproduce in a dirty
environment. We get infected with various diseases in a dirty
environment. Therefore, we should keep our environment clean.

Wastes and their types

Wastes are the materials that

are no longer needed and are

thrown away. Food wrappers,

pieces of glasses, used papers

and polythene bags, peels of

fruits and old clothes are some
Fig.
Fig.examples of wastes. Wastes

are produced from houses, 7.3 Waste materials
factories, offices, schools,
hospitals, etc. Waste materials

are classified into two types, viz. (a) Biodegradable wastes and

(b) Non-biodegradable wastes.

a. Biodegradable wastes

The wastes that decompose due to the action of microorganisms
are called biodegradable wastes. The wastes produced from
plants and animals are biodegradable wastes. Waste food, peels
of fruits, animal excreta and vegetable wastes are some examples
of biodegradable wastes. Dead bodies of plants, animals and dry
fallen leaves are also biodegradable wastes.

7.4 Kitchen wastes Compost wastes
Biodegradable wastes

54 GREEN Science Health and Physical Education Book-3

Biodegradable wastes can be reused to get biogas and compost
manure. We can produce compost manure by decaying
biodegradable wastes. Compost manure is used to increase the
fertility of the soil.

b. Non-biodegradable wastes

The wastes that do not decompose for a long time are called non-
biodegradable wastes. Used plastics, old glass bottles, used metal
cans, plastics and food wrappers are some examples of non-
biodegradable wastes. These wastes do not decay in soil for a long
time. These wastes cause environment pollution and degrade the
quality of soil.

Non-biodegradable wastes Fig.
are the major causes of
environmental pollution. 7.5
Therefore, we should limit
the use of non-biodegradable Non-biodegradable wastes
wastes. Similarly, we should
dispose non-biodegradable
wastes properly.

Environmental Pollution

The addition of harmful and unwanted substances in the
environment is called environmental pollution. Various
human activities are responsible for environmental pollution.
Both biodegradable wastes and non-biodegradable wastes
cause environmental pollution. The waste materials that cause
environmental pollution are called pollutants. Sewage, garbage,
used plastics, smoke and dust are some examples of pollutants.

Environmental pollution is mainly divided into three types :

a. Air pollution b. Water pollution

c. Land pollution

GREEN Science Health and Physical Education Book-3 55

a. Air pollution

Air is the mixture of different gases like nitrogen, oxygen, carbon
dioxide, etc. We need fresh air to breathe. But the air that we breathe,
mainly in city areas, is not clean. Air contains smoke, harmful gases
and dust particles which make air impure. The contamination of
air with harmful and unwanted substances is called air pollution.

Smoke produced from

automobiles, factories, burning

of firewood, etc. and dust

particles cause air pollution.

Similarly, bad smell coming Fig. Fig.

out of waste materials, garbage,

and dead animals also cause air 7.6 Air pollution
pollution.

Air pollution causes various diseases like bronchitis, lungs cancer,

asthma and tuberculosis. It also causes skin diseases, cough and

suffocation. Therefore, we should try to reduce air pollution. We

should use public vehicles instead of private vehicles to reduce air

pollution. Similarly, industries should be located away from the

human settlement to reduce air pollution.

b. Water pollution

Living beings cannot survive

in the absence of water. Water

is one of the most essential

substances for the existence of

life. Various human activities

and mixing of waste materials Water pollution
in water cause air pollution. 7.7
The contamination of water

with harmful and unwanted substances is called water pollution.

The sewage produced from the human settlement and industries
is the main cause of water pollution. Polluted water affects both
plants and animals.

56 GREEN Science Health and Physical Education Book-3

Fig.7.8Polluted pondPolluter water tap
Fig. Polluted river

The major causes of water pollution include defecating and
urinating in the sources of water, disposal of sewage into the
sources of water, discharging of untreated wastes and sewage into
the sources of water, bathing of humans and cattle in the sources
of water, washing vehicles and throwing wastes in the sources of
water. Similarly, excessive use of chemical fertilizers, insecticides
and pesticides also cause water pollution.

The consumption of polluted water causes various diseases like
cholera, typhoid, diarrhoea, dysentery and jaundice. Therefore,
consumption of polluted water should be avoided. We should not
pollute the sources of water. Similarly, we should not throw waste
materials into the sources of water.

c. Land pollution

Land occupies about one-third

part of the earth's surface. Land

is formed by soil and rocks

Different types of plants and

animals grow, live and die on

land. Various human activities 7.9 Land pollution
are responsible for land

pollution. The contamination of land with harmful and unwanted

substances is called land pollution. Land is being polluted day by

day due to human activities.

The major causes of land pollution include (i) dumping of household
wastes like glasses, bottles, plastics, metals, papers, etc. on soil,

GREEN Science Health and Physical Education Book-3 57

(ii) improper disposal of industrial and agricultural wastes,
(iii) excessive use of chemical fertilizers, insecticides, pesticides,
etc. and (iv) improper disposal of garbage and sewage on soil.

Polluted land causes contamination of ground water, contamination
of crops, contamination of water resources, etc. It also affects the
habitat of organisms. Polluted land affects all plants and animals.
Therefore, we should try to reduce land pollution. Similarly, we
should reduce the overuse of chemical fertilizers and insecticides.

Methods of reducing environmental pollution

Environmental pollution can be reduced by adopting the following
methods.
1. Overuse of automobiles should be reduced.
2. Factories and industries should be established away from

human settlements.
3. Kitchen and garden wastes should be disposed properly.
4. Degradable wastes should be used to produce compost manure.
5. Non-biodegradable wastes should be disposed properly.
6. Overuse of chemical fertilizers and insecticides should be reduced.
7. Afforestation should be encouraged and deforestation should

be discouraged.
8. Defecation on open places should be avoided.
9. Wastes should be reused and recycled.
10. Drainage should be managed properly.

Exercise

1. Tick (√) the best answer from the given alternatives.

a. Environment is made of .......................

living things non-living things

living things and non-living things

58 GREEN Science Health and Physical Education Book-3

b. The environment containing waste materials is called a
....................... environment.

clean dirty healthy

c. The contamination of water with waste materials is called
....................... pollution.

water land air

d. We should try to reduce ....................... pollution.

air environmental land

2. Put a tick (√) for the correct statement and a cross (×) for the
incorrect one.
a. The environment which is free from waste materials is called
clean environment.

b. Non-biodegradable wastes decompose due to the action of
micro-organisms.

c. Polluted air causes various diseases like bronchitis and
asthma.

d. Factories should be established away from the human
settlement.

3. Fill in the blanks using appropriate words.

a. The wastes that do not decompose are called ......................

b. Smokes and dust particles cause ...................... pollution.

c. Polluted water causes diseases like ...................... and
......................

d. The contamination of land with waste materials is called
......................

GREEN Science Health and Physical Education Book-3 59

4. Answer the following questions.
a. What is environment? Write down the components of the
environment.
b. What is meant by a clean environment?
c. What is meant by a dirty environment?
d. What are wastes? Write their types.
e. What are biodegradable wastes? Write with examples.
f. What are non-biodegradable wastes? Write with examples.
g. What is environmental pollution?
h. What are pollutants? Give any two examples.
i. What is air pollution? Write any two causes of air pollution.
j. Write any two effects of air pollution.
k. What is water pollution? Write any two causes and two
effects of water pollution.
l. What is land pollution? Write any two causes and two effects
of land pollution.
m. Write any five methods to reduce environmental pollution.

5. Study the given figures and write the types of pollution.
a. b. c.

Project work
Pay a visit in your surroundings and observe the environment.

Find out whether the environment is clean or dirty.
Visit a nearby source of water and observe whether the water

is polluted or not.

60 GREEN Science Health and Physical Education Book-3

Matter unit

8

Weighting Distribution (Approximate)
Teaching periods : 3 Marks (in %): 4.5

Learning Objectives

After completing the study of this unit, students will be able to:
(i) introduce matter with examples.
(ii) explain types of matter, viz. solid, liquid and gas

with examples.
(iii) define floating and sinking matter, soluble and

insoluble matter, transparent and opaque objects,
conductors and insulators with examples.

Word Power solid liquid
matter shape size
gas definite floating
volume transparent opaque
sinking insoluble conductors
soluble
non-conductors

Teaching Instructions

ó Introduce matter to the students with examples.
ó Ask the students to name different types of matter.
ó Introduce three states of matter, viz. solid, liquid and gas to the students

with their characteristics.
ó Introduce floating and sinking matter to the students with examples.
ó Explain transparent and opaque objects to the students with examples.
ó Introduce conductors and nonconductors to the students with examples.
ó Evaluate the students asking them various questions related to matter.

GREEN Science Health and Physical Education Book-3 61

Matter

A variety of things are found around us. Air, water, soil, stone, and
wood are some of the substances found in our surroundings. These
substances have weight and occupy space. The substance that has
weight and occupies space is called matter. Some of the common
matter found around us are shown below :

Stone Water Air

Fig.

8.1 Wood Petrol
Brick

States of Matter

Matter present around us exists in three states. They are (i) solid (ii)
liquid and (iii) gas.

a. Solid

Substances like stone, wood, brick and paper have definite
shape and volume. The substances having a fixed shape
and volume are called solids. Solids are hard and rigid.

62 GREEN Science Health and Physical Education Book-3

Fig. Fig.8.2 Brick Wood Book

Stone

b. Liquid

Substances like water, kerosene, milk, petrol, oil and diesel occupy
space but do not have a fixed shape. These substances are called
liquids. The substances having a fixed volume but no fixed shape
are called liquids.

8.3 Kerosene Petrol Water

Milk

The shape of a liquid changes according to the shape of the vessel in
which it is kept. However, the volume of a liquid does not change
no matter what type of container we keep it in. Similarly, liquids
can be poured from one container to another.

Activity 1

Take a glass and add 50 ml water in it. Observe the shape of
water in the glass.

Now, pour the water in some other containers like beaker, jug,
bottle and bowl. Observe the shape of the water in each of the
given containers.

Measure the volume of the water in each of the containers.
Does the volume change in each container? Write down the
conclusion of this activity.

This activity proves that liquids have no fixed shape but have a
fixed volume.

GREEN Science Health and Physical Education Book-3 63

c. Gas

Air is the mixture of different gases. Nitrogen, oxygen, carbon
dioxide, water vapour, etc. are found in air. These gases neither
have a fixed shape nor a fixed volume. The substances which neither
have a fixed volume nor a fixed shape are called gases. Examples:
air, smoke, water, vapour, etc.

Fig.

8.4 Gas cylinder Tube

Balloon

Gases can be compressed inside the cylinder, balloon, football,
basketball, tubes of vehicles, etc.

Activity 2

Take a big balloon and inflate it with more and more air to
make it very big.

Observe the volume and shape of the inflated balloon. Can
you see the air inside the balloon?

Now, prick the balloon with a needle. What is the shape and
size of the balloon? What can you conclude from this activity?

Floating and Sinking Objects

Some substances like ice, dry wood, plastic and leaves float in
water. These substances are lighter than water. The substances that
are lighter than water float on water.

Substances like stone, brick, glass, iron and marble sink in water.
These substances are heavier than water. The substances that are
heavier than water sink in water. Can you name some substances
that sink in water?

64 GREEN Science Health and Physical Education Book-3

Fig. Fig. Fig.8.5 Wood floating on water Iron nail sinking in
Ice floating on water water

Soluble and Insoluble Matter

When some sugar is added in water and stirred with a spoon, the
sugar dissolves in water. Similarly, salt, alum, copper sulphate, etc.
also dissolve in water. These substances are called water soluble
substances. Thus the substances that dissolve in water are called
soluble substances.

8.6 Common salt Copper sulphate Alum
Sugar

Some substances like stone, iron, wood, plastic, glass, brick and
sand do not dissolve in water. These substances are called water
insoluble substances. The substances that do not dissolve in water
are called water insoluble substances. Can you name some more
substances that do not dissolve in water?

8.7
Brick Stone Iron Sand

GREEN Science Health and Physical Education Book-3 65

Transparent and Opaque Objects

Some substances like glass, air, clean water and thin plastic allow
light to pass through them. These substances are called transparent
objects. Thus, the objects which allow light to pass through them
are called transparent objects.

Some objects like wood, brick, paper, metal, thick plastic and rock
do not allow light to pass through them. These objects are called
opaque objects. The objects that do not allow light to pass through
them are called opaque objects.

Conductors and Non-conductors

We use metal containers to cook food and boil water and milk. Our
cooking utensils are made of iron, aluminium, copper, brass, etc.
When the base of these utensils is heated, heat is passed through
them. These substances are called conductors. The substances which
pass heat and electricity through them are called conductors. All
metals like iron, copper, aluminium, silver and gold are conductors
of heat and electricity.

Fig.

8.8 Kettle Electric iron
Cooking utensils Pressure cooker

The substances which do not pass heat and electricity through
them are called non-conductors. Dry wood, paper, plastic, brick,
rubber, etc. do not allow heat and electricity to pass through them.
So these substances are called non-conductors or insulators. Non-
conductors like plastic, wood, paper, etc. are used to cover the
handles of cooking utensils and electric wires.

66 GREEN Science Health and Physical Education Book-3

Fig.

8.9 Dry wood Paper
Plastic

Activity 1

Observe various substances kept at your home. Classify these
substances in terms of solid, liquid and gas.

Activity 2

Prepare a list of objects that float and sink in water.
Prepare a list of transparent and opaque objects, conductors

and non-conductors.

Activity 3
Take some sugar, salt, sand and soil.
Put these substances in water one by one and stir.
Find out which of these substances dissolve in water.

Exercise

1. Tick (√) the best answer from the given alternatives.

a. The substance that has weight and occupies space is called ......

solid matter liquid

b. Which of the following substances is a solid?

milk air stone

c. Liquids have a fixed volume but no fixed .......................

shape size colour

GREEN Science Health and Physical Education Book-3 67

d. Iron and copper are ....................... of heat.

non-conductors conductors insulators

2. Put a tick (√) for the correct statement and a cross (×) for the
incorrect one.
a. Anything that has weight and occupies space is called
matter.

b. Solids have fixed shape but no fixed volume.

c. Sugar and salt dissolve in water.

d. Silver and gold are conductors of heat and electricity.

3. Fill in the blanks with appropriate words.
a. ........................ occupies space and has weight.
b. The substances that are lighter than water ........................ in
water.
c. The objects which allow light to pass through them are called
........................
d. ........................ allow heat and light to pass through them.

4. Answer the following questions.
a. What is matter? Give any three examples.
b. Name the three states of matter.
c. Define solids with any three examples.
d. What are liquids? Write any three examples.

68 GREEN Science Health and Physical Education Book-3

e. Define gases with any three examples.
f. What types of substances float in water? Name any two

objects that sink in water.
g. What are soluble substances? Name any two insoluble

substances.
h. What are transparent and opaque objects? Give any two

examples of each.
i. Define conductors with any two examples.
j. What are non-conductors? Give any two examples.

5. Identify solid, liquid and gas from the following.

i. Milk ii. Wood iii. Paper

iv. Oxygen v. Kerosene vi. Brick

vii. Air viii. Petrol ix. Stone

6. Match the following. Milk
a. Solid Air
b. Liquid Stone
c. Gas Opaque
d. Copper Conductor
e. Glass Transparent
f. Wood

GREEN Science Health and Physical Education Book-3 69

Importance of Air unit

9

Weighting Distribution (Approximate)
Teaching periods : 2 Marks (in %): 3

Learning Objectives

After completing the study of this unit, students will be able to:
(i) introduce air and state its composition.
(ii) describe the importance of air.

Word Power importance occupy
air vapour atmosphere
space mountaineer cylider
storms inflate
trekking

breeze

Teaching Instructions

ó Start teaching asking the students some questions related to air.
ó Introduce air to the students.
ó Demonstrate an activity to give the concept of air to the students.
ó Explain the composition of air.
ó Describe the importance of air with examples.
ó Evaluate the students asking them various questions related to the

importance of air.

70 GREEN Science Health and Physical Education Book-3

Air

Air is the mixture of different gases. Different gases present in the
air include nitrogen, oxygen, carbon dioxide, etc. Water vapour and
dust particles are also found in the air. Air cannot be seen but its
presence can be felt. Have you ever seen the leaves of tree shaking
due to the movement of air?

Fig.
Fig.
9.1 Wind mill
Leaves shaking by air Air filled in balloons

The surface of the earth remains

surrounded by a layer of air. This

layer of air is called atmosphere. The

amountofairdecreaseswhenwegoup

in high mountains. So mountaineers

feel difficulty while climbing up high

mountains. Therefore, they carry

oxygen cylinders while trekking. Air 9.2
has weight and it occupies space. It
moves from one place to another. Air A mountaineer carries
moves gently as well as with a high an oxygen cylinder
speed. The air that moves gently is while climbing up a
mountain.

called a breeze. It makes us cool and fresh. Slow moving air is also

called a wind. Sometimes air moves very fast with a high speed. It

is called storm. The wind that moves with a high speed is called a

storm. It blows papers, dust, clothes and roofs of houses. It may

break tree branches, uproot trees and blows the roofs of houses.

Therefore a storm may be dangerous. We should stay indoors and

be careful during a storm.

GREEN Science Health and Physical Education Book-3 71

Fig.9.3
Fig. Effects of air

Importance of Air

Air is a very important matter for living beings. Plants and animals
cannot survive in the absence of air. The importance of air is given
below:

1. All living beings need air (oxygen) to

breathe.

2. Green plants use air (carbon dioxide)
to prepare food by photosynthesis.

3. Air is essential to run wind mills.

4. Air is essential to burn substances.

5. Air is used to inflate balloons, balls

and tyres of vehicles. 9.4

6. Air helps to dry wet clothes. Paragliding

7. Air is essential for paragliding and flying kites.
8. Air is essential for flying aeroplanes and helicopters.

Exercise

1. Tick (√) the best answer from the given alternatives.

a. The mixture of different gases is called .......................

air water wind

b. The thick layer of air that surrounds the earth's surface is
called .......................

hydrosphere atmosphere wind

72 GREEN Science Health and Physical Education Book-3

c. Air is the ....................... state of matter.

solid liquid gaseous

d. Green plants use ....................... gas to prepare food.

oxygen carbon dioxide nitrogen

2. Put a tick (√) for the correct statement and a cross (×) for the
incorrect one.

a. Air is the mixture of different gases.

b. The amount of air increases when we climb up a mountain.


c. The slow moving air is called a breeze.

d. Wind mills run with the help of air.

3. Fill in the blanks using appropriate words.
a. ....................... is the thick layer of air that surrounds the
earth's surface.
b. The air that moves with a high speed is called .......................
c. ....................... is used to inflate balloons.
d. ....................... makes us cool and fresh.

4. Answer the following questions.

a. What is air? Write any two properties of air.
b. Name any three gases present in the air.
c. Define atmosphere.
d. What is meant by wind and storm?
e. Write any two effects of a storm.
f. Write down the importance of air in any four points.

GREEN Science Health and Physical Education Book-3 73

Windy Day unit

10

Weighting Distribution (Approximate)
Teaching periods : 2 Marks (in %): 3

Learning Objectives

After completing the study of this unit, students will be able to:
(i) differentiate between wind and storm.
(ii) state the effects of wind and storm.
(iii) compare the positive and negative aspects of wind

and storm.

Word Power storm breeze
windy uproot pollen grains
pleasant injured

pollination

Teaching Instructions

ó Start teaching asking the students various questions related to wind
and storm.

ó Introduce a windy day to the students with some examples.
ó Introduce breeze or wind and storm to the students.
ó Differentiate between wind and storm.
ó Explain the effects of storm to the students.
ó Describe the importance of wind in brief.
ó Evaluate the students asking them different questions related to a

windy day.

74 GREEN Science Health and Physical Education Book-3

Windy Day

Wind or breeze is the air that moves slowly and gently. The day
with slow moving air is called a windy day. Leaves of plants, dust
particles, pieces of paper, polythene bags and food wrappers move
here and there on a windy day. We feel cool and comfortable in a
windy day. Clothes and grains dry easily on a windy day. We feel
pleasant and easy to breathe on a windy day.

Fig.10.1Wind blows plastic and Wind blows clothes.
Fig. Wind blows tree food wrappers.
branches.

Storm Storm

A storm is the air that moves
with a high speed. Storm blows
off dust particles, dry leaves,
papers, plastics and other
things at a high speed. A storm
is very forceful and strong. A
storm is very destructive in
nature. It generally occurs on 10.2
hot summer days.

Occurrence of a storm

The air on the surface of the earth gets heated due to strong heat
of the sun during hot summer days. The hot air becomes light and
rises up creating a gap. The cold air rushes down to fill the gap. As
a result, a storm takes place.

GREEN Science Health and Physical Education Book-3 75

Effects of a storm

1. A strom carries dust

particles, paper,

plastics, etc. and Fig.

causes air pollution.

2. The dust particles 10.3 Effects of storm
carried by a storm

may enter our eyes. It may cause eye problems.

3. A storm may blow away the roofs of houses made of tins and
tiles. It may hit a person walking nearby the house and causes
accidents.

4. A storm may uproot trees or break the branches of trees on the
road side. It may cause road accidents.

5. A storm damages flowers, fruits and crops.

6. A storm may carry away the clothes kept on the roof top for
drying.

7. In deserts, storm carries away a large amount of sand from one
place to another forming sand dunes.

Importance of wind

Strong wind affects plants, animals and man-made structures. But
slow moving air, i.e. wind is very important for plants and animals.
In hot summer days, we feel comfortable when wind blows. The
cold wind flowing from the cold regions makes the environment
pleasant. Wind carries pollen grains from one plant to another and
helps in pollination. It increases the productivity of crops. Wind
helps to dry our wet clothes.

Activity 1

Have you ever faced a storm? Write any three adverse effects of
the storm that you have observed or faced.

76 GREEN Science Health and Physical Education Book-3

Fig.

10.4 Wind helps in pollination.
Wind helps to dry our wet clothes.

Exercise

1. Tick (√) the best answer from the given alternatives.

a. The slow moving air is called .......................

breeze storm both

b. Breeze or wind makes the environment .......................

hot rainy cool

c. A storm generally occurs on ....................... days.

hot summer cold winter rainy

d. A ....................... affects plants, animals and man-made
structures.

wind breeze storm

2. Put a tick (√) for the correct statement and a cross (×) for the
incorrect one.
a. The day with slow moving air is called a windy day.
b. During a storm, air moves very slowly.
c. A strom generally occurs on hot summer days.
d. A strom cannot uproot trees.

GREEN Science Health and Physical Education Book-3 77

3. Fill in the blanks using appropriate words.
a. ..................... is the air that moves slowly and gently.
b. ..................... is very destructive in nature.
c. ..................... may blow away the roofs of houses.
d. In desert, ..................... are formed due to storm.

4. Answer the following questions.
a. What is wind or breeze?
b. What is a windy day?
c. What is a storm? How does it occur?
d. Write any four effects of a storm.
e. Write down any two importance of wind.

5. Observe the given figure and write down the main cause of
it.

78 GREEN Science Health and Physical Education Book-3

Cold Day unit

11

Weighting Distribution (Approximate)
Teaching periods : 1 Marks (in %): 1.5

Learning Objectives

After completing the study of this unit, students will be able to:
(i) introduce a cold day.
(ii) state the types of clothes that are worn on cold days.

Word Power winter fog
cold invisible frost
inactive escape extreme
snow migrate communicable
polar visibility
skid

Teaching Instructions

ó Start teaching asking the students some questions related to a cold day.
ó Introduce a cold day to the students with some examples.
ó Explain the features of a cold day to the students.
ó Describe how surroundings become cold during winter.
ó Describe why we wear warm clothes during winter.
ó Explain adverse effects of cold weather.
ó Evaluate the students asking them different questions related to a cold

day.

GREEN Science Health and Physical Education Book-3 79

Cold Day

A day with cold weather is a cold day. Most days of the winter
season are very cold. We feel difficult to work on cold days. Many
animals hide in their shelters on cold days. We wear warm clothes
on cold days to keep our body warm. We go in the sun and near
the fire to protect ourselves from cold. We also use electric heaters
to keep our rooms warm. In the terai region of Nepal, some people
die due to extreme cold in the winter season. Many trees shed their
leaves during the winter season.

Fig. Fig.11.1 We use an electric Leaves fall in winter.
We sit near fire on cold heater to get warm.
days.

In the winter season, snow fall occurs in mountains and high hills.
Due to extreme cold, water turns into ice during winter. In cold
mornings, fog covers the surroundings and reduces visibility. Frost
can also be seen in cold days of the winter season.

11.2 Foggy day Frost on cold days
Snow fall in mountains

In the winter season, we feel very cold in high hills and mountains
due to snow fall. Snow is the frozen form of rain. People living in
mountains migrate to lowlands, i.e. hills during winter.

In the winter season, there is less chance for the spread of
communicable diseases. However, most people suffer from
common cold, pneumonia, etc. In winter, we should wear warm

80 GREEN Science Health and Physical Education Book-3

woolen clothes to protect our body from extreme cold. We wear
clothes like jacket, sweater, gloves, cap, trousers, socks, mittens, etc.

Fig. Fig.11.3 Sweater Woolen cap Gloves
Jacket

When the fog covers the surroundings and reduces visibility, there
is a great chance of road accidents. In some places, snow covers the
roads and affects the traffic. Vehicles moving on ice may skid and
meet with accidents. We suffer from frostbite in the winter season.
Our fingers and toes get badly affected due to frostbite. Some
people die due to extreme cold in the winter season.

11.4 Snow affects the traffic Frost bite in winter
Vehicles skid on ice. on the road.

Activity 1

Have you experienced very cold days in the winter season? Name
the clothes that you wear in the winter season.

Exercise

1. Tick (√) the best answer from the given alternatives.

a. We feel very cold in the ....................... season.

summer winter spring

b. Snowfall generally occurs in .......................

plains hills mountains

GREEN Science Health and Physical Education Book-3 81

c. We wear ....................... clothes in the winter season.

woolen cotton light

d. We suffer from ....................... during the winter season.

diarrhoea common cold cough

2. Put a tick (√) for the correct statement and a cross (×) for the
incorrect one.
a. Most days of the winter season are very hot.

b. In the winter season, fog reduces visibility.

c. We wear warm clothes in the winter season.

d. We suffer from frostbite in the summer season.

3. Fill in the blanks using appropriate words.
a. Most days in winter are ......................
b. ...................... is the frozen form of rain.
c. ...................... affects our fingers and toes.
d. We suffer from the common cold during ......................

4. Answer the following questions.
a. What is a cold day?
b. Write any two features of a cold day.
c. Why do we wear warm clothes in winter?
d. When do we see the frost?
e. What is snow? Where does snow fall occur in winter?
f. Why do road accidents occur in winter?
g. Name any two diseases that are common during winter.

82 GREEN Science Health and Physical Education Book-3

Water unit

12

Weighting Distribution (Approximate)
Teaching periods : 2 Marks (in %): 3

Learning Objectives

After completing the study of this unit, students will be able to:
(i) describe the sources of water.
(ii) introduce the three states of water.
(iii) explain the water cycle that occurs in nature.
(iv) describe the importance of water.

Word Power underground springs
surface reservoir tube well
spouts convert freezing
boring evaporation vaporization
melting hydroelectricity
condensation

Teaching Instructions

ó Introduce water and describe its sources to the students.
ó State and explain the three states of water.
ó Explain the water cycle to the students demonstrating its figure.
ó Demonstrate evaporation and vaporization to the students.
ó Explain the importance of water to the students.
ó Ask various questions related to water and water cycle to evaluate the

students.

GREEN Science Health and Physical Education Book-3 83

Water

Water is the most important substance essential for survival of
living beings. Plants and animals cannot survive without water.
About two-thirds of the earth's surface remain covered with water.
Water exists in solid, liquid and gaseous states in nature. However,
we use the liquid state of water the most. Water is also found in the
bodies of living organisms.

Occurrence of Water

The place from which we get water are called sources of water.
Water is found on the surface as well as inside the earth's surface.

a. Surface water
Surface water is the water present on the surface of the earth. It
consists of water present in river, pond, lake, ocean, etc.

Fig.

12.1 Phewa Lake Ocean
Koshi River

Rivers originate from the Himalayas and finally all the rivers get
mixed in the ocean. In the rainy season, the level of water increases
in rivers during heavy rainfall. Melting of ice in the Himalayas due
to heat of the sun is the main causes of formation of rivers. Rivers
always flow from higher level or the lower level. Lakes and ponds
are formed by collection of rainwater or collection of water from
rivers and streams. Ponds are smaller while lakes are larger in size.

Water remains in the form of ice in the Himalayas and high
mountains. The ice melts due to heat of the sun and flows downwards

84 GREEN Science Health and Physical Education Book-3

in the form of rivers. Most of the rivers of Nepal originate from the

Himalayas. Saptakoshi, Saptagandaki and Karnali are some famous

rivers of Nepal. Do You Know

The process in

which water

changes into ice

Fig. Fig. is called freezing.

12.2 The process in
Gandaki River
Karnali River which ice changes
into water is

Water is also found in the air in the called melting.

form of vapour. The water present in

ocean, river, lakes, ponds, etc. gets heated due to the heat of the sun

and changes into vapour. The process in which water changes into

vapour is called evaporation. Clouds are formed due to evaporation

of water.

12.3 Evaporation of water
Formation of cloud

Water exists in all the three states, viz. solid, liquid and gas. In solid
state, water is found in the form of ice or snow in the Himalayas.
When water is cooled, it changes into solid state, i.e. ice. In liquid
state, water is found in oceans, rivers, lakes, ponds, streams, etc.
Similarly, water is found in liquid state under the earth's surface.
When water is heated, it changes into vapour, i.e. gaseous state.

GREEN Science Health and Physical Education Book-3 85

Fig.12.4
Fig. Fig.Ice (solid state of water) Water in liquid state Water vapour (gaseous
state of water)

Underground water
Water present under the surface of the earth is called underground
water. It comes out through spouts and springs. We can get
underground water through well, tube well, handpump, etc.

12.5 Spring Tube well
Spouts

Water Cycle

The water present

on the surface of the

earth gets heated due

to the heat of the sun

and forms vapour.

This vapour moves

up in the sky and

forms clouds. When Water cycle
clouds are cooled, 12.6
water again falls

down in the form of rain. This process is called the water cycle.

86 GREEN Science Health and Physical Education Book-3

So, the water cycle is the cyclic Do You Know
movement of water from earth's
surface to the atmosphere and back The process in
to the earth's surface again. Let us which water vapour
describe the water cycle that occurs in changes into water
nature. Water is found in liquid state droplets is called
in oceans, rivers, ponds, lakes, etc. condensation.

Due to the heat from the sun, water on seas, rivers, ponds and lakes

gets heated and forms water vapour. The vapour goes up in the

atmosphere and cools down to form water droplets. This process is

called condensation.

Numerous droplets of water join together and form clouds. When

clouds are cooled, water falls down in the form of rain. Black and

dark clouds carry more water than white clouds. So, heavy rainfall

occurs when the sky is covered with dark clouds. In the water cycle,

water from the earth's surface goes up in the sky and again falls

down on the earth's surface in the form of rain. The water cycle is a

continuous process that occurs in nature.

Fig.

12.7

Clouds in the sky Rainfall

In the Himalayas, the weather is extremely cold. So snowfall occurs

in the Himalayas instead of rainfall. Due to extreme cold, water

droplets change into snow. Sometime, hailstones fall along with

rain. Hailstones are the balls of ice that fall downwards the earth.

When raindrops pass through a very cold layer of air, they freeze

and form small or big balls of ice. Hailstones damage flowers,

fruits, vegetables and crops. Therefore, hailstones are not good for

farmers.

GREEN Science Health and Physical Education Book-3 87

Fig.12.8Crops damaged by hailstones
Fig. Fig. Hailstones

Importance of Water

1. Water is essential for the survival of plants and animals.
2. Water is used by green plants to prepare food.
3. Water is used for drinking.
4. Water is used for bathing, swimming and washing clothes.

12.9 Swimming Transportation
Drinking water

5. Water is used for boating
and shipping.

6. Water is used to generate
hydroelectricity.

7. Water is used for cooking
food and cleaning things.

8. Water is used for

irrigating crops. 12.10

Hydroelectricity power plant

88 GREEN Science Health and Physical Education Book-3

Exercise

1. Tick (√) the best answer from the given alternatives.

a. Water is essential for survival of .......................

plants animals living beings

b. Water remains in the form of ice in the .......................

Himalayas hills plains

c. Water exists in ....................... states in nature.

one two three

d. Water is used for .......................

drinking washing

drinking and washing

2. Put a tick (√) for the correct statement and a cross (×) for the
incorrect one.
a. About two-thirds of the earth's surface are covered with
water.

b. The process in which ice changes into water is called
melting.

c. Ice is the liquid state of water.

d. Hailstones damage crops, fruits and vegetables.

3. Fill in the blanks using appropriate words.
a. Rivers originate from the ......................
b. We can get underground water through ...................... and

GREEN Science Health and Physical Education Book-3 89

......................
c. In the Himalayas, ...................... occurs instead of rainfall.
d. ...................... is used to generate hydroelectricity.
4. Answer the following questions.
a. What is surface water? Name any three sources of surface

water.
b. What is meant by underground water? How can we get

underground water?
c. What are the three states of water?
d. What is water cycle?
e. Define condensation and evaporation.
f. What are hailstones? How are they formed?
g. Why are hailstones bad for farmers?
5. Draw a neat figure showing the water cycle.
6. Name the process shown in the given figure.

7. Write down the utilities of water in any five points.

90 GREEN Science Health and Physical Education Book-3

The Earth unit

13

Weighting Distribution (Approximate)
Teaching periods : 15 Marks (in %): 23

Learning Objectives

After completing the study of this unit, students will be able to:
(i) introduce the earth and name various layers of the

earth.
(ii) introduce various landforms, viz. plain, hill, valley,

mountain and plateau and differentiate among them.

Word Power atmosphere planet
minerals crust mantle
hydrosphere uniform plain
core valley mountain
hill deposition fertile
plateau geological vegetation
elevation

Teaching Instructions

ó Start teaching by asking the students some questions related to the
earth.

ó Introduce 'earth' to the students and explain its features.

ó Demonstrate the picture showing different layers of the earth.

ó Demonstrate various layers of a boiled egg to the students and compare
these layers with the layers of the earth.

ó Introduce plain, hill, valley, mountain and plateau to the students.
Explain their features and differentiate among them.

ó Evaluate the students asking them various questions related to the
earth and its structure.

GREEN Science Health and Physical Education Book-3 91

The Earth

The earth is our home planet. Fig. The Earth
All plants and animals live onFig.
the earth. The earth is round in
shape like an orange. However,
it appears flat as we see only a
small portion of it. The surface
of the earth remains covered
with a thick layer of air called
atmosphere. The average 13.1
temperature on the surface of
the earth is 15°C. The earth is
made of rocks, soil, water, air, minerals, etc.

More than two-thirds Crust Inner core
of the earth's surface Outer core
remain covered with
water and the rest is
covered with land.
The layer of water
present on the earth is
called hydrosphere.

The inner part of the Mantle

earth can be divided 13.2

into three different Internal structure of the earth

layers. These layers are crust, mantle and core. The crust is the

outermost rocky layer of the earth, the mantle is the middle layer

and the core is the innermost layer of the earth. The core is further

divided into outer core and inner core.

Structures of the earth's surface

The structure of the earth's surface is not uniform. It has various
landforms with different altitude. The land surface of the earth can
be divided into plain, hill, valley, mountain and plateau.

92 GREEN Science Health and Physical Education Book-3

a. Plain

The terai region of Nepal is an
example of a plain area. The flat
surface of the earth with low
height is called the plain. There
is plenty of water and fertile soil
in plains. Therefore, plains are
suitable for farming. Generally,
plains are warmer than hills 13.3
and mountains.
Fig. Plain (Terai)
Fig.
b. Hill

Hill is the area of the land that is higher than the land around it.
The height of a hill is less than that of a mountain. Nepal is a hilly
country. Most of the land surface of Nepal is covered with hills
of different heights. Hills are colder than plains and warmer than
mountains. Hills are less fertile than plains. However, different
types of birds, animals and vegetation are found in hills.

Do You Know

Different types of
fruits, vegetables,
birds and medicinal
plants are found in the
hilly regions of Nepal.

13.4
Hill

c. Valley

The low-lying area of land surrounded by hills is called a valley.
The soil of valley is fertile. So it is suitable for crop production.
Kathmandu valley, Dang valley and Pokhara valley are some valleys
of Nepal. Human sattlement is denser in valleys than that in hills.

GREEN Science Health and Physical Education Book-3 93

Fig.
Fig.
13.5 Kathmandu valley
Dang valley Mountain

d. Mountain

Mountain is the area of land
which is higher than hill. There
are many mountains in Nepal.
The highest mountain in the
world, i.e. Mt. Everest is also
located in Nepal. Mountains
are not suitable for human
settlement and crop production.
Mountains are very cold as 13.6
compared to hills and plains.
Generally, mountains remain
covered with ice.

5. Plateau

A plateau is the area of flat land Fig.
that is higher than the land
around it. The Tibetan plateau Tibetan plateau
is the highest plateau in the
world. It is also called the roof
of the world. Human settlement,
forests and wild animals are also
found in plateaus. Generally,
plateaus are used for agriculture 13.7
and human settlement.

94 GREEN Science Health and Physical Education Book-3

Activity 1

Name the landform where you live. List the plants and animals
found there. Also, write any two features of that landform.

Exercise

1. Tick (√) the best answer from the given alternatives.
a. The shape of the earth is .......................

round circular flat

b. More than two-thirds of the earth's surface are covered with
.......................

soil water air

c. The terai region of Nepal is an example of a .......................

hill valley plain

d. ....................... are not suitable for human settlement and
crops.

Mountains Hills Plains

2. Put a tick (√) for the correct statement and a cross (×) for the
incorrect one.
a. The layer of water present on the earth's surface is called
atmosphere.

b. Plains are warmer than hills.

c. Valleys are more fertile than hills.

d. Mt. Everest is the tallest mountain in the world.

GREEN Science Health and Physical Education Book-3 95

3. Fill in the blanks using appropriate words.
a. The layer of air that surrounds the earth's surface is called
.........................
b. ......................... is the innermost layer of the earth.
c. The low-lying area of land surrounded by hills is called
.........................
d. ......................... is also called the roof of the world.

4. Answer the following questions.
a. What is the shape of the earth?
b. What is atmosphere?
c. What is meant by hydrosphere?
d. What are three layers of the earth?
e. What is plain? Write its two features.
f. What is a hill? Write its two features.
g. Define valley and mountain. Name the tallest mountain in
the world.
h. What is a plateau? Name the highest plateau in the world.

5. Name the land forms given below. Also, write any two features
of each.
a. b.

96 GREEN Science Health and Physical Education Book-3

Information and unit
Communication
14

Weighting Distribution (Approximate)
Teaching periods : 4 Marks (in %): 6

Learning Objectives

After completing the study of this unit, students will be able to:
(i) introduce information and communication.
(ii) name different means of information and

communication.
(iii) state the importance of communication.

Word Power communication news
information television internet
radio messenger dissemination
knowledge facebook twitter
technology advertisement document
library

Teaching Instructions

ó Start teaching by showing some means of information and
communication like newspaper, mobile phone, computer, etc.

ó Introduce information and communication to the students.

ó Explain various means of information and communication to the
students.

ó Describe the importance of information and communication to the
students.

ó Ask various questions related to information and communication to
evaluate the students.

GREEN Science Health and Physical Education Book-3 97

Information and Communication

Information is the accumulated knowledge or details about
somebody or something. We read books and newspapers, watch
television and listen to the radio to get information on different
things. Similarly, we browse the Internet to collect information of
various fields. Books, newspapers, television , radio, Internet, etc.
are the sources of information. Communication is the process of
expressing ideas and feelings or giving people information. Means
of communication play a vital role to disseminate information to
make people aware and well informed.

The materials that provide knowledge on somebody/something are
called sources of information. Books, newspaper, hoarding boards,
posters, radios, television, internet, etc. are the main sources of
information.

Fig.

14.1 Watching TV Talking on mobile phone

Reading a newspaper

We read books to get information on various things. We read
newspapers to get information related to different subjects or
fields. We can go to a library to read books and newspapers to get
information on various things. Therefore, books, newspapers and
libraries are various sources of information.

We listen to the radio and watch television to get information on
current affairs, weather forecasting, sports, advertisements, etc.

98 GREEN Science Health and Physical Education Book-3

Fig.

14.2 Hoarding board

Poster

We see posters or hoarding boards placed on the poles, walls, rooftops
or on the side of roads. These materials contain advertisement of
some products, companies or institutions to market their goods or
services.

Activity 1

Listen to the radio or watch television at 7:00 am in the morning.

Write the news that you have listened or watched and report it
to your teacher.

Read a newspaper and copy a piece of news in your notecopy
and submit it to your teacher.

Means of Information and Communication

We write and send letters to communicate with our relatives or friends
when they are far from home. We can send a particular information to
many people at the same time through newspapers, radio, television,
etc. Information published on newspapers reaches different places
and people get information reading those newspapers. Similarly,
we watch television or listen to the radio to get information about
different things. Now-a-days, we use telephone, mobile, facebook,
twitter, etc. to communicate with one another.

GREEN Science Health and Physical Education Book-3 99

Telephone Mobile Facebook

Fig.14.3YahooG-mail
Fig.
Twitter

We use telephone and mobile phone to talk with family members
or friends when they are far from us. Telephone and mobile phone
work if the network is available. The network is distributed through
telecommunication stations. Fax is used to transfer important
documents from one place to another in a very short time. Telephone
network is required to operate fax. It is mostly used in offices.

Now-a-days, computer is widely Fax machine
used as a means of communication.
Computer can be used for chatting,
sending e-mails and videos, playing
games, listening to music, watching
videos, writing and storing documents,
etc. Using Internet, we can send e-mails 14.4
or chat with our friends and family
members. Have you sent an e-mail to
anybody so far? Have you used Internet so far?

100 GREEN Science Health and Physical Education Book-3