Passport-G3-Textbook-Science-FY

SCIENCE TEXTBOOK Class 3 Name: ___________________________________ Section: ________________ Roll No.: _________ School: __________________________________

Preface IMAX partners with schools, supporting them with learning materials and processes that are all crafted to work together as an interconnected system to drive learning. IMAX presents the latest version of the Passport series – updated and revised after considering the perceptive feedback and comments shared by our experienced reviewers and users. Designed specifically for CBSE schools, the Passport series endeavours to be faithful to the spirit of the National Curriculum Framework (NCF) 2005. Therefore, our books strive to ensure inclusiveness in terms of gender and diversity in representation, catering to the heterogeneous Indian classroom. The larger aim of the NCF 2005 regarding science teaching is to acknowledge and address the dynamic nature of science by focusing on the development of skills to acquire and process information scientifically. The Passport EVS/Science textbooks and workbooks for CBSE schools offer the following features:  Interactive content that engages students through a range of open- ended questions that build curiosity and initiate scientific exploration  Opportunities for experimentation, analysis and synthesis of ideas and concepts  Exposure to locally relevant environmental problem solving  Effective use of visual elements to enable learning of structures, processes and phenomena  A focus on science-specific vocabulary building  Integrated education of values and life skills  Promotion of participatory and contextualised learning through the engagement of all relevant stakeholders in the learning process Overall, the IMAX Passport EVS/Science textbooks, workbooks and teacher companion books aim to enhance the development of scientific temper along with the inculcation of healthy habits, skills and values that promote environmentally sensitive and culturally responsive democratic citizenship among students. – The Authors

I Will Learn About I Remember Contains the list of learning Introduces new concepts to build on the objectives to be achieved in the prerequisite knowledge/skills required to lesson understand and apply the objective of the topic I Think Pin-up Note Introduces the concept/subtopic and arouses Contains key retention points from the curiosity among students concept Train My Brain I Understand Checks for learning to gauge the Explains the aspects in detail understanding level of students that form the basis of the concept I Apply Includes elements to ensure that students are engaged Connects the concept to throughout real-life situations by enabling students to apply what has been Be Amazed learnt through the practice questions Fascinating facts and trivia related to the concept Connect the Dots I Explore (H.O.T.S.) A multidisciplinary section that Encourages students to extend connects a particular topic to the concept learnt to advanced other subjects in order to enable application scenarios students to relate better to it A Note to Parent Inside the Lab To engage a parent in Provides for hands-on experience out-of-classroom learning of their with creating, designing and child and conduct activities implementing something given in the section to reinforce innovative and useful the learnt concepts Corr Pages_Science_PPS_G3_TB_Features page (13-12-17).pdf 1 13-Dec-17 5:20:45 PM

Contents Class 3 1 My Hobbies����������������������������������������������������������������������������������������������������������������� 1 2 Family as First School ������������������������������������������������������������������������������������������������� 7 3 Organ Systems����������������������������������������������������������������������������������������������������������� 11 4 Skeletal System���������������������������������������������������������������������������������������������������������� 15 5 Way around Our Neighbourhood���������������������������������������������������������������������������� 20 6 Forms of Water������������������������������������������������������������������������������������������������������������ 25 Inside the Lab – A�������������������������������������������������������������������������������������������������� 30 Activity A1: Salt from Sea Water Activity A2: Create Your Compass 7 Sources of Light���������������������������������������������������������������������������������������������������������� 32 8 Composition of Air����������������������������������������������������������������������������������������������������� 36 9 Stems and Leaves������������������������������������������������������������������������������������������������������ 40 1 0 Uses of Animals���������������������������������������������������������������������������������������������������������� 45 Inside the Lab – B��������������������������������������������������������������������������������������������������� 52 Activity B1: My Lava Lamp Activity B2: Leaves Leaves Everywhere! 1 1 Food Diversity������������������������������������������������������������������������������������������������������������� 54 1 2 Types of Houses���������������������������������������������������������������������������������������������������������� 60 1 3 Travel with Family������������������������������������������������������������������������������������������������������� 65 1 4 Communication without Speaking�������������������������������������������������������������������������� 69 Inside the Lab – C������������������������������������������������������������������������������������������������������������� 74 Activity C1: Cuisines of Different States Activity C2: Make Your Script

Lesson My Hobbies 1 I Will Learn About R hobbies and their types. U how hobbies are useful to us. A choosing a hobby as a job. H my parents’ hobbies. I Think Sam likes to watch movies in his free time. His sister likes photography. They enjoy doing these activities. What are such activities, other than your studies, called? I Remember You go to school every day to learn new things. You play with your friends at school. What do you do after school? At home, you do homework, watch TV, play and help your parents. How do you spend your free time on Sundays and holidays? 1

different types of activities Some of the activities that you may enjoy doing are shown below. Guess what they are. 2

They are called hobbies. Hobbies are the activities that we do for relaxation when we have free time. There are different types of hobbies. They are shown in the chart given below: Types of hobbies sports outdoor arts collection making and recreation games painting coins scrapbook birdwatching singing stamps making football stargazing gardening reading and leaves knitting badminton writing feathers pottery cooking cricket dancing video games travelling photography yoga trekking The activities that people enjoy doing running mountaineering during their free time are called hobbies. swimming adventure sports I Understand HOW ARE HOBBIES HELPFUL TO US? People take up hobbies to be happy. But there are other benefits of hobbies too. Some of the benefits are as follows: 1) They keep us healthy: Hobbies like exercising, sports and games keep us healthy. 2) They help us to be creative: Hobbies like painting, writing and cooking help us to create something new. 3) They help us to make useful things: Hobbies like knitting and pottery help us to make useful things. 4) They help us to learn new things: Hobbies like reading books helps us to learn new things. A collection of stamps and coins helps us learn about different countries. 5) They teach us to work in groups: All hobbies which involve group activities teach us to work in groups. For example, games like football, hockey and so on. Group dancing also helps us learn to work in groups. My Hobbies 3

Train My Brain 1) What type of hobby is pottery? 2) What type of hobby is mountaineering? I Apply You have learnt about the benefits of hobbies. Do all your friends have the same hobbies? One of your friends may like to play video games. Another friend may like to play badminton. Do you and your siblings playing video game playing badminton like the same games or activities? Some of your choices may be the same and some may be different. What could be the reason? People choose a hobby that they find interesting. Different people have different likes and dislikes. Therefore, different people have different hobbies. If we practise a hobby for a long time, we become good at it. Then, we can carry forward that hobby as a job. For many people, their hobbies become their jobs when they grow up. For example, V. V. S. Laxman, the Indian cricketer, was good at studies. However, he became a great batsman as playing cricket V. V. S. Laxman J. K. Rowling was his hobby. The famous author of Harry Potter - J. K. Rowling - wrote stories as a hobby. Her hobby has become her job. 4

Discuss your hobbies with your friends. Make a list of one another’s hobbies. Write what your friends want to become when they grow up. Your friends’ hobbies What your friends want to become Be Amazed Did you know that collecting stamps is called the king of all hobbies? It is one of the most popular hobbies in the world. a collection of stamps I Explore (H.O.T.S.) Everyone has hobbies. What hobbies do your parents have? Did they have hobbies similar to yours when they were of your age? What could be the reason behind this? Find out. Connect the Dots English Fun Find the names of hobbies hidden in these jumbled letters: 1) rwadngi: ___________________________ 2) sngigni: ___________________________ 3) ottpery: ___________________________ 4) goya: ___________________________ My Hobbies 5

Social Studies Fun Some people collect coins and stamps to learn about different places or people. What is the hobby of collecting coins called? coins A Note to Parent Discuss your child’s hobbies with him or her. Tell him or her the importance of having a hobby. 6

Lesson Family as First School 2 I Will Learn About R habits and values. U how habits and values differ in families. A habits and values in my family. H good and bad habits. I Think Arnav was playing near his house. He saw an old lady walking with a stick. The stick fell from her hand. Arnav picked up the stick and gave it back to her. Who taught him to do so? I Remember We live with our family members. We spend most of our time with them. So, we learn a lot from them. What do we learn from our family? Habits: These are activities that we eating sleeping running do daily. People have different habits. For example, eating, walking, talking, sleeping and so on. 7

Values: These are good actions and thoughts. Values help us to decide what is right or wrong. For example, respecting elders, taking care of younger ones and so on. We learn different habits and values from our family. respecting elders taking care of younger ones I Understand Some habits that we learn from our family members are: • the type of food we like to eat • the way we eat • table manners • the time we go to bed and wake up • how loudly or softly we talk or laugh learning table manners from parents How do we learn different values from our family? Being kind and helpful: What happens when you are sick? Your family takes care of you. Respecting others: Your parents talk to elders with respect. They listen to what the elders say. Being disciplined: Your parents get up on time and do the household work. They help you get ready for school. Then, they go to work. They have taught you to wake up early and not be late for school. • Does your family behave in the same way as your friends’ families? No, you will find some differences. Habits and values within families are different. In some families, the family members: • touch the feet of elders • stand up when elders enter the room 8

• keep footwear outside the house praying before • eat meals and celebrate festivals together a meal • pray before meals and so on Do your family members follow any of these practices? Train My Brain 1) Who is the last person you helped? 2) List any three habits of your family. I Apply You have read about the habits and values we learn from our families. What are the good habits and values that you have learnt from your family? Who is the family member you respect the most? Why do you respect him or her? Whom do you respect other than your family members? Some people you respect are your school principal, teachers, helpers, drivers, cleaners and so on. All of them help to run the school. Do you think that all the things we learn from others can be good for us? Do your parents or teachers say that you have learnt some bad habits? How can we make sure that we learn throwing garbage fighting and shouting only good things from others? Find out around with the help of your teachers and parents. Be Amazed Did you know having breakfast is a healthy habit? Children who have breakfast everyday can study and play better than others! Family as First School 9

I Explore (H.O.T.S.) Write a letter to a family member. Talk about the good habits and values you have learnt from that person. Thank him or her for it. Also, write about any bad habits he or she should quit. Connect the Dots English Fun Write a poem about the family member you like the most. (Hint: My mother I like my mother She takes care of me) Maths Fun Ayan returns from school by 3 o’clock in the afternoon. He spends time with his grandma till dinner. If Ayan eats dinner at 8 o’clock, how many hours does he spend with her? A Note to Parent giving a glass of going with grandmother water to grandfather on her morning walks Encourage your children to help elders at home with small but important jobs. (Hint: Giving a glass of water to grandfather/grandmother before and after meals, helping them in their morning and evening walks and so on.) 10

Lesson Organ Systems 3 I Will Learn About R organs inside the body. U different organ systems and their parts. A the effect of daily activities on organ systems. H the position of different organs inside the body. I Think When we breathe in, we take in air. Where does this air go? It goes inside our body. Let us find out what is inside our body. I Remember We have some special body parts. The parts of the body that help us to do special and important work are called organs. We see some organs from outside. However, there are some organs that are inside the body. We cannot see them. food pipe ORGANS INSIDE OUR BODY Food pipe: It is a tube, which leads from the mouth, stomach through the throat to the stomach. Stomach: It is a sack-like organ. When we eat food, it food pipe and stomach goes into the stomach through the food pipe. 11

Windpipe: It is a tube that connects the throat windpipe to the lungs. It is also called the trachea. Lungs: There is a pair of lungs in the chest. H eart: It is located a little to the left of the lung middle of our chest. It is about the size of our fist. lungs heart Kidneys: We have a pair of kidneys. They are bean-shaped. Brain: It is present inside the head. Some organs inside our body form a group to kidneys brain do specific tasks. Such a group of organs is called an organ system. There are many such The groups of organs organ systems. inside the body that do specific tasks are Examples of some organ systems are the digestive called organ systems. system, circulatory system, skeletal system, muscular system and so on. I Understand SOME IMPORTANT ORGAN SYSTEMS Our body has many organs and organ systems. They work food pipe together to carry out different tasks. stomach intestines The digestive system helps to take in food through our mouth digestive system and foodpipe. In our stomach, food is broken down to make it easy to digest(just like a mixer-grinder). The digestive heart system consists of the mouth, food pipe, stomach and intestines. blood vessels The respiratory system helps in breathing. The organs of this system are the nose, windpipe and lungs. circulatory system The circulatory system sends blood to all parts of the body. The heart is the most important organ in this system. It pumps blood to all the parts of the body just like a water pump. Blood flows through the blood vessels(thin tubes like water pipes). 12

Our brain controls all activities of our body. It helps us to think and learn. The brain is a part of the nervous system. Train My Brain 1) What is the shape of the kidneys? 2) Where does the food go after you put it in your mouth? I Apply Now, you know about the different organ systems and how they work. Can we control all these organs? We cannot directly control the organs inside our body. The brain works even when you are sleeping. You breathe continuously when you are running, eating or sleeping. Is the breathing faster or slower when you are doing these activities? The heart beats continuously. Does the heart rate remain the same or does it change? Be Amazed A child’s heart beats faster than an adult’s. Your heartbeat changes depending on the type of music you are listening to. I Explore (H.O.T.S.) Draw an outline of the human body on a cardboard and cut it out. Then, draw the different organs present inside our body on a piece of paper. Colour them. Cut out the organ shapes. Can you place these organ shapes correctly on the cutout of the body? To do this activity, you will need: a piece of cardboard, a piece of paper, pencil, crayons, scissors, gum cutout of the body and organs Organ Systems 13

Connect the Dots English Fun You know that the word ‘organ’ means body parts having a specific work. What is the other meaning of this word? Maths Fun Suppose your heart beats 90 times a minute. How many times will it beat in 10 minutes? A Note to Parent Discuss with your child the importance of eating healthy food. Explain to him or her how it helps the organs to work properly. For example, research shows that eating food items like walnuts, egg yolks and dark chocolates can make our brain healthy. These food items help us to increase our memory power. Help your child to find out food items that keep our other organs like the stomach, heart and kidney healthy. walnuts egg yolk dark chocolate 14

Lesson Skeletal System 4 I Will Learn About R the skeletal system. U the functions of the skeletal system. A keeping our bones healthy. H the skeletal system in animals. I Think Asif fell while cycling. He hurt his leg. His mother took him to the doctor. The doctor asked them to get an x-ray picture of the leg. Do you know what an x-ray picture tells us? an x-ray picture of the leg I Remember Hold your wrist. Do you feel something hard inside it? It is a bone. Our body has many such bones. At birth, we have around 300 bones. As we grow, some bones fuse and join. Adults have 206 bones. Joints are places where two bones meet. Example: knee, elbow All the bones in our body together form the skeletal system. 15

IMPORTANT PARTS OF THE SKELETAL SYSTEM skull rib cage Skull: Bones in the head form the skull. backbone (vertebrae) Ribs: Bones around the chest form the ribs. The ribs join in the front and back, to form a rib cage. human skeletal system Backbone: Many small bones join to form a rod- like structure called the backbone. It connects the neck to the lower The skeletal system is made back of our body. up of bones. It is also called the The three important parts of vertebrae. the skeletal system are the skull, the rib cage and the backbone (vertebrae). I Understand FUNCTIONS OF THE SKELETAL SYSTEM 1) The skeletal system gives shape and support to our body. For example, skull bones give shape to our head and face while the backbone helps us to stay erect. Imagine how your body will be without a backbone! Bones store minerals inside them. These minerals make them strong enough to support our body. 2) It protects the organs inside our body. For example, the rib cage protects the lungs and the heart while the skull protects the brain. skull rib cage brain lung heart skull rib cage 16

3) The skeletal system helps us to move. Joints help our body to twist and turn. For example, leg joints help us to walk and run. Train My Brain 1) Which part of the skeletal system protects the brain? 2) Which part of the skeletal system protects the heart and lungs? I Apply HOW CAN WE KEEP OUR BONES STRONG AND HEALTHY? Healthy food: Vitamins and minerals like calcium make our bones strong. So, we must eat food items which contain these nutrients. Leafy vegetables, pulses and milk products are rich in calcium and vitamins. leafy vegetables pulses milk products Good posture: We should always sit straight in the upright posture to keep our bones strong. Exercise and play: Playing and exercising regularly keeps our bones strong and healthy. WHAT IS A FRACTURE? good and bad postures Sometimes bones may get hurt because of accidents or a bad fall on the playground. In such cases, the bones may crack or break. This crack or break is called a fracture. How can we know if there is a fracture in our bone? For this, an x-ray picture is taken. It helps the doctor to see the fracture in the bones. The doctor will then put a plaster around it. The plaster keeps fracture the bone in the correct position and helps in healing. Skeletal System 17

plaster plaster helps to heal the fracture Be Amazed The smallest bone in our body is found in our ear. This bone is called the stapes. The longest bone in our body is the thigh bone or femur. femur I Explore (H.O.T.S.) shell tortoise You have learnt that humans have a skeletal system inside their body. Some animals have an exposed skeletal system. earthworm Have you seen a tortoise? It has a hard cover or shell on its body. The shell of a tortoise is an example of an exposed skeletal system. Make a list of animals having such shells. You must have seen many creepy crawlies like earthworms around your house. Do they have skeletal systems? Connect the Dots Maths Fun An adult human has 27 bones in one hand and 30 bones in one leg. What is the total number of bones in one hand and leg? 18

Social Studies Fun Monkeys and humans have a similar skeletal system. A Note to Parent Talk to your child about the food that keeps bones healthy. Encourage him or her to have more calcium-rich food items like: • milk, curd, cheese and other milk products • green vegetables such as broccoli and cabbage • soya beans and soya drinks • nuts • bread • fish such as sardines Skeletal System 19

Lesson Way around Our 5 Neighbourhood I Will Learn About r directions and sub-directions. u identifying directions. a mapping our neighbourhood. h the use of a compass. I Think Can you help the puppy to find its way home? To reach its house the dog needs to know where to take the correct turns. Similarly, we also need to know our way to visit places in our neighbourhood or inside our school. How do we find our way? I Remember What do we need to know to go to any place? We should know the address and where it is located. When we tell someone how to go to a place, we give directions. While giving directions, we use words like left, right, straight and so on. We use these words in relation to a landmark. 20

A A landmark is a well-known place in an area that can turn left turn right go straight go past cross be easily seen. It can be ahead identified from a distance. DIRECTIONS AND SUB-DIRECTIONS N We also give directions using the four main directions – north (N), W E east (E), west (W) and south (S). There are also four sub-directions that lie between these main directions. They are north-east, north- west, south-east and south-west. S north north- north- west east west east south- south- west east south directions and sub-directions I Understand finding directions How do you know which is the North and which is the East? Let us do an activity to find directions. Stand facing the Sun when it rises. That direction is the East. Open your arms as shown in the picture. The direction behind you is the West. Your right- hand shows the South. Your left-hand shows the North. Way around Our Neighbourhood 21 Corr Pages_Science_PPS_G3_TB_Pg 21 (13-12-17).pdf 1 13-Dec-17 5:24:39 PM

These directions and sub-directions help us to know places in our neighbourhood. They also help us to read maps of our city, district, state and so on. Train My Brain 1) Which sub-direction lies between the East and South? 2) In which direction does the Sun rise? I Apply To read a map, you need to know the directions that you have learnt. A map is given below. It shows a ‘house’. Riya lives in this house. Her house is east-facing. She wants to go to the post office to post a letter to her friend. Let us help Riya. West South North East map Since Riya’s house is east-facing, she faces the East when she steps out. The directions are as follows: • Step out of the house and go to the road on your left. • Turn west. • Walk westward on the road. • Turn left towards the South at the end of the road. • The post office is at the corner of the road. Is there any other way to reach the post office? Discuss with your friends. 22

Be Amazed An interesting way of remembering directions is: Never Eat Slimy Worms N = North, E = East, S = South, W = West I Explore (H.O.T.S.) One more way of finding directions is to use a compass. It is a device used to find directions on the surface of the Earth. It has a needle which always points towards the north-south direction. It is mainly used in ships to understand the direction. compass Connect the Dots Social Studies Fun Uttar Map of western India is shown here. Find out: Pradesh a) State to the north of Gujarat b) State to the south of Madhya Pradesh Rajasthan Gujarat Madhya Pradesh N WE Maharashtra S English Fun Prepositions of place A AB A ABC at the between corner of next to B opposite Way around Our Neighbourhood 23

A Note to Parent Play a game of ‘Treasure Hunt’ with your child. Hide a gift in your house. Draw a map leading to the gift. Ask your child to find the gift using the map. Hint: A bunny is fast not I know this is fun like a SNAIL. When you and you think it’s NEAT. get a letter they come Look in a place where in the MAIL. you sit to EAT. Follow the clues Your very last clue... to a gift for YOU. Try not to PEEP. The first one is easy. Are you feeling tired? It’s in your SHOE. It’s time to SLEEP. START END a treasure hunt map 24

Lesson Forms of Water 6 I Will Learn About R forms of water. U the water cycle. A changing water forms around us. H how salt is got from sea water. While going to school, Aslam saw a puddle on the road. But I Think while coming back from school, he found that it had dried up. How did the water disappear? puddle I Remember We hang clothes out in the sun to dry. Why do wet clothes dry after some time? Heat from sunlight changes the water in the clothes to clothes hung in the sun water vapour. The water vapour moves out of the clothes and the clothes dry. We can also see water change into vapour when we boil water. water vapour When cooled, water vapour changes into water. My Hobbies 25

Very cold conditions change water to ice. We find ice inside refrigerators and in very cold places around the world. ice ice-covered land On heating, ice melts to form water. Let us now learn about the three forms of water. What are the differences melting ice water between water, water vapour and ice? Water exists in three different forms. Ice has a shape. It does not Water and its forms have no flow. colour, smell and taste. Water flows downwards. Water flows and does not have a shape of its own. Steam moves upwards. It takes the shape of the vessel it is kept in. Water Ice has shape. always flows downwards. Water vapour has no shape. It always moves upwards and mixes with the air around. All three forms of water have no colour, smell and taste. I Understand We get water from rain. The rainwater gets collected in water bodies like rivers, ponds, lakes and so on. Some of the water that goes into the soil is stored underground. During daytime, heat from the Sun changes the water of the water bodies into vapour form. The water vapour thus formed goes upwards and cools down. 26

It forms small water droplets. These water droplets (with other things) form clouds in the sky. Inside the clouds, the water droplets combine to form big drops. When the water drops in the clouds become heavy, they fall as rain. During winter, in some very cold places, water changes to ice and snow. Thus, water changes its form and always moves from the water bodies to the clouds and back. This movement is called the water cycle. It makes water available to all living things. Clouds Rain Water vapour water cycle Train My Brain 1) Which form of water can move upwards? 2) Which form of water has its own shape? I Apply We have read that clouds give us rain. How do rain clouds look like? Rain clouds are dark in colour. They are heavy and filled with water droplets. clouds rain clouds ForMmys oHfoWbbaiteesr 27

Why is it that all clouds do not come down as rain? Find out. sea-shore Have you ever been to a sea-shore? We sweat a lot when we water droplets on a are at the sea shore. Do you know the reason for this? At sea- glass of cold water shores, the air is filled with water vapour. So, the water in our sweat does not get changed into vapour easily. Have you seen dew drops on leaves in the morning? Where do they come from? Some water vapour is always present in the air around us. It cools down when it touches any cold surface. This is the reason why we see water droplets on a glass of cold water. We learnt that wet clothes dry due to the heat from the Sun. How do wet clothes dry when we keep them indoors? In monsoon, clothes dry with difficulty. Why is it so? Be Amazed Fog is a cloud that appears very close to the ground. fog I Explore (H.O.T.S.) Do you know that common salt is prepared from sea water? Sea water contains a lot of salt. So, it is unfit for drinking. This salt can be separated out. For this, the sea water is collected in open ponds. Due to the heat from the sunlight, the water changes into vapour. The salt which remains in the ponds is collected and purified to be used as common salt. sea water collected in ponds 28

Connect the Dots English Fun Anu is a drop of water. She lives in a pond. Anu was feeling very hot on a hot summer afternoon. She decided to travel. Can you tell where Anu will go from the pond, on a bright, sunny afternoon? (Hint: Anu is a water droplet. What happens to a water droplet when the weather is hot? It follows the water cycle. Now complete the story of Anu!) Maths Fun An open tank has 750 litres of water in it. Every day, 5 litres of water changes into the vapour form. How many days will it take for the tank to dry up? A Note to Parent Show your child day-to-day life examples involving changes in the forms of water. ForMmys oHfoWbbaiteesr 29

Inside the Lab – A Make sure you do these activities only with the help of a teacher or an adult. Activity A1: Salt from Sea Water In the lesson ‘Forms of Water’, we learnt that water exists in three different forms. Let us see how we get salt from sea water due to the changing forms of water. You will need: sea water collected in ponds salt, some tap water, a saucepan, spoon, stove, tray and a black plastic sheet. You need to: 1) add two cups of water to the pan. Place it on the stove. Let the water boil. 2) add salt to the hot water in the pan. Mix it well with a spoon. Salt dissolves faster in hot water. Continue adding salt until it stops dissolving in the hot water. Eventually, you’ll reach a point at which the salt won’t dissolve anymore, no matter how hot the water is. When you reach that point, turn the stove off and let the water cool slightly. 3) spread the black plastic sheet inside the tray. 4) pour the water from the pan into the tray. 5) keep the tray out in the sun for two days. black plastic paper and tray (The location should be chosen wisely to prevent the setup from any external damage.) The water will change into water vapour. This will leave behind crystals of salt in the tray. They are small and shiny. Salt is prepared from sea water in a similar way. Sea water changes into water vapour during summer, leaving behind salt. 30 12/22/2017 3:39:04 PM NR_BGM_182110021-Passport-G3-Textbook-Science-FY_Txt_Corrected page.pdf 1

Activity A2: Create Your Compass The magnetic compass is used to detect or find out directions: north, south, east and west. It has a magnetic needle that points to the north. You can easily make your own compass. You will need: compass a bar magnet, needle, cork disc, cup/bowl/glass, pair of pliers and water You need to: 1) rub a magnet over the needle about twenty times. Always rub in the same direction. 2) cut off a small portion from one end of the cork, magnet about 1 inch thick, making a small cork disc. This needle 4 step should be done with the help of the teacher. 3) put the cork disc on a flat surface. Carefully push the needle through the side of the disc as shown in the picture. Use the pair of pliers to push the needle. This step should be done only with the help of the teacher. 4) fill a deep cup, glass or bowl with water till at least half full. 5) place the cork disk on the surface of the water. Try to keep the disc floating in the centre of the water, away from the sides of the cup. 6) place your compass on a flat surface and watch what happens. What does the needle do? When it stops moving, which direction does it point towards? Inside the Lab – A 31 NR_BGM_182110021-Passport-G3-Textbook-Science-FY_Txt_Corrected page.pdf 2 12/22/2017 3:39:04 PM

Lesson Sources of Light 7 I Will Learn About R natural and artificial sources of light. U discovery of fire as a source of light. A electricity as a source of light. H light as heat. I Think Nowadays, we see electric bulbs everywhere. What did your grandparents use to light up their homes when they were young? I Remember Our eyes help us to see the things around us. But why are we unable to see in the dark? This is because our eyes can help us to see things only in the presence of light. Where do we get light from? We get light from two different sources: 1) natural sources   2) artificial sources or man-made sources 32

Natural sources: These sources include heavenly bodies like the Sun and the stars. The Sun is the most important natural source of light. the stars the Sun Artificial sources: The artificial sources of light are made by human beings. They include electric bulbs, kerosene lamps, oil lamps, candles and so on. electric bulb kerosene lamp oil lamp candle I Understand flint stones firewood In ancient times, there were no artificial sources artificial light sources of light. Human beings could only hunt and then and now gather food during the day time. Then, humans discovered fire by rubbing flint stones. This helped them to get light even after sunset. They could also guard their caves from dangerous animals with the help of fire. Earlier, humans would burn firewood for light. Time went on. Then they started using oil lamps, candles and lanterns like we do today. After the discovery of electricity, humans started using electric lamps as a source of light. Train My Brain 1) Name any two natural sources of light. 2) Give examples of light sources which we use nowadays. Sources of Light 33

I Apply What type of sources of light should we use? We should try to use sunlight, which is the main source of natural light, to the maximum. It is the cheapest source of light. We can use solar panels to capture light and convert it to solar panels electricity. This electricity can be used to light our homes in the night. Artificial sources of light like electric bulbs need electricity to give out light. This electricity is limited. So, we should use light sources which use less electricity. For example, LED bulbs, tube lights and CFL bulbs. Moreover, we should switch off the lights when LED and CFL bulbs not in use. kerosene Some artificial sources of light cause harm to the environment. For lamp example, kerosene lamps give out smoke. We should try to avoid the use of such harmful sources. Be Amazed Have you seen fireflies? They are insects that give out light from their bodies. Some aquatic animals like jellyfish also give out light. firefly jellyfish I Explore (H.O.T.S.) Many light sources also give us heat. We use fire for cooking as it provides heat. We can use sunlight for heating water and cooking food with the help of solar heater and solar cooker. 34

solar water heater solar cooker Connect the Dots Maths Fun Sunlight takes about 8 minutes and 20 seconds to travel from the Sun to the Earth. How many seconds does it take for sunlight to reach the Earth? English Fun Using a dictionary, find out the different meanings of the word ‘light’. A Note to Parent Discuss the importance of saving electricity with your child. Encourage all family members to switch off lights when no one is in the room. Sources of Light 35

Lesson Composition of Air 8 I Will Learn About R air as a mixture. U sources of components of air. A air pollution. H the bad effects of burning firecrackers. I Think Arjun woke up early in the morning to go to school. He found that the air was fresh and cool. When he came back from school in the afternoon, he felt the air was not so fresh and cool. Do you know why? I Remember We know that air is all around us. Air is a mixture of different gases. Gases are substances that can move around freely. Gases do not have any shape of their own. They can fill any available space of any shape. Oxygen, carbon dioxide and nitrogen are the main gases present in the air. Air is mostly made up of nitrogen and oxygen. Carbon dioxide and some other gases are present in smaller amounts. The air around us is Air also contains water vapour, which is the gaseous form of a mixture of different water, and some dust. gases, water vapour and some dust. Clean air does not have any smell or colour. 36

I Understand We have learnt that air contains carbon different gases. Let us find out dioxide the sources of these gases. We all need air to breathe. All animals breathe in oxygen and oxygen give out carbon dioxide. At the same time, plants take in carbon dioxide from the air to make their food. They give out sources of oxygen and carbon dioxide in air oxygen during this process. In this way, the levels of oxygen and carbon dioxide in the air are maintained. What will happen to this balance, if we cut trees unnecessarily? We know that water vapour in the air comes from different water bodies. Once the air gets filled with water vapour, it changes into water droplets and falls as rain. Train My Brain 1) Name one gas present in the air. 2) Name a form of water present in air. I Apply Sometimes the air gets filled with smoke and dust. The presence of such harmful substances in the air is called air pollution. Substances which make the air dirty (or pollute the air) are called pollutants. Let us find out the sources of these pollutants. firewood kerosene vehicles lamp When we burn firewood or a kerosene lamp, it gives out smoke. Smoke from vehicles and factories also pollute the factory air. Vehicles also blow up dust in the air. Carbon dioxide is useful at very low levels. But when its amount increases above normal levels, it becomes a pollutant. Composition of Air 37

Any colour or bad smell of air shows air pollution. Polluted air is unhealthy. It may damage our lungs and eyes. It makes us feel tired and sick. If the air is polluted, we should wear masks. Masks filter the air and allow only clean air to enter our nose. How can we keep the air clean? child wearing a mask 1) Plant trees: Plants absorb carbon dioxide and give out oxygen. They help to maintain the air clean and healthy. So, we feel fresh when we are in a field, garden or a forest. It is, therefore, important to plant trees. 2) Use smoke-free lamps and stoves: We should avoid using cooking stoves and lamps which give out smoke. 3) Stop burning garbage: We should not burn garbage in our neighbourhood. Plastics in the garbage give out harmful gases on burning. 4) Use well-maintained vehicles: Vehicles that are not maintained or are old give out harmful gases. Be Amazed As we go higher, the level of oxygen in the air decreases. So, the people who climb mountains carry oxygen cylinders with them. I Explore (H.O.T.S.) People burst firecrackers (crackers) on festivals and special occasions. Do you think firecrackers are good for the environment? Firecrackers are made up of chemicals which catch fire easily. They make a lot of noise. They also add harmful smoke to the air causing air pollution. People who make firecrackers in factories suffer from skin and lung problems. firecrackers people who make firecrackers 38

It is dangerous to work in places where they are made or stored. Still, at some places, even small children are forced to work in firecracker factories. We should, therefore, stop bursting firecrackers. Connect the Dots English Fun An abbreviation is a short form of any word or a phrase. We can write the names of different gases using abbreviations as given below. Component of air Abbreviation Carbon dioxide CO2 Nitrogen N2 Oxygen O2 You will learn about these symbols in higher classes. Social Studies Fun Smoke from factories is harmful to us. So, factories are built in industrial areas far from our homes. Find out whether there is any such area near your city. A Note to Parent Make your child understand the importance of clean air. Help him or her notice the difference in air quality during different times of the day. You may use the following examples to understand the change in the air quality: 1) with vehicles and without vehicles on the road 2) with firecrackers and without firecrackers on Diwali 3) with and without the smoke coming out from the factories and so on Talk about the lives of people who work in firecracker factories. Also, discuss the side effects of burning firecrackers. Composition of Air 39

Lesson Stems and Leaves 9 I Will Learn About R different types of stems and leaves. U functions of stems and leaves. A uses of stems and leaves. H why plants shed leaves. I Think Nitin’s teacher showed him four types of leaves. She asked him to find the differences between them. What differences did Nitin find? I Remember You have learnt about various types of plants. You have also learnt that a plant has different parts. Now, let us learn about the stems and leaves of plants in detail. THE STEM stem leaf The stem is usually seen above the ground. It is generally green when young and later becomes woody and dark brown. The stem is different in different types of plants. 40

The stem of a big tree is called the trunk. tree trunk stem with stem without Stems may be with branches or without branches branches branches. For example, mango trees have branches but coconut trees have no branches. Stems are usually erect, but in some plants they can be creeping or twisted. For example, pumpkin plants have creeping stems. The stem of the rose plant has thorns on creeper stem thorns on a hair on the it. In some plants, stems are covered with of pumpkin rose stem stem of a tulsi small hair. plant The stem of the bamboo is smooth, while the stem of the mango tree is rough. We have learnt about the different types of stems in plants. Now, let us learn about the different kinds of leaves. THE LEAVES Leaves are important parts of plants, just like the bamboo stems rough stem or bark of a mango tree stems. They are of different size, shape and colour. They are arranged in different ways in different plants. Let us take a look at some leaves. Banana plants have big leaves and tulsi plants have small ones. Peepal trees have heart-shaped leaves. Shapes Arrangement Edges Lotus plants have round ones. hand Some leaves have toothed edges. Example: neem shaped Some leaves have a special smell. Example: tulsi spear simple smooth shaped compound toothed The stem is usually seen above the ground and bears branches, heart leaves, flowers and fruits. shaped The leaves are of different round shape, size, colour and have different arrangements. needle lobed compound different types of leaves Stems and Leaves 41

I Understand We have learnt about different types of stems and leaves. But, why do plants need stems and leaves? Let us see how stems and leaves are helpful to plants. Functions OF STEMS 1) The stem allows the plant to stand upright and holds up the branches and leaves. It holds the leaves in such a way that they trunk helps the tree can get maximum sunlight. to stand upright 2) The stem carries water and nutrients from the roots to the leaves. It carries food prepared in the leaves to the different parts of the plant. 3) Some stems store food for the plant. Example: sugarcane sugarcane FUNCTIONS OF LEAVES Plants need food to live. Leaves make food for the plant. They also help plants to breathe. How do leaves make food? To make food, leaves need sunlight, water sunlight oxygen and carbon dioxide gas. They use the water carbon dioxide carbon dioxide gas from the air. Water from the roots reach the leaves through the stem. In the presence of sunlight, leaves combine water and carbon dioxide to make food. During this process, they give out oxygen. So, they are called ‘the kitchen of the plant’ or ‘food factories of the plant’. Train My Brain 1) Give an example of a plant that has a thorny stem. 2) Name a plant with heart-shaped leaves. 42

I Apply We have learnt about the functions of stems and leaves. Now, let us see how we use stems and leaves in our day-to-day life. Uses of stems Some stems are used: • as food, for example, potato and onion. The sugarcane stem is used to make juice, sugar and jaggery. • to make furniture as they are hard and strong. Teak and mahogany are a few examples. • to make medicines. Example: tulsi, neem • to make useful things like rubber and jute. The milky juice from the stem of the rubber tree is used to make rubber. The stem of the jute plant is used to make jute. We make ropes and bags using jute. Uses of leaves Some leaves are used: • as food. Leafy vegetables such as spinach and parsley are some examples. Leaves of the tea plant are used to make tea. • as spices in cooking. Example: bay leaves, coriander • to make medicines, for example, the leaves of the tulsi and bay leaves neem plants. • to cook and serve food. Example: turmeric leaf, banana leaf • as decorations during festivals cooking food using a leaf serving food on a leaf and special occasions. Be Amazed The green colour of leaves is due to a substance called chlorophyll. Leaves turn brown due to a substance called tannin. Tannin also gives the colour to your tea. Stems and Leaves 43

I Explore (H.O.T.S.) During the winter season, some trees shed all their leaves. Leaves of some trees also change their colour. Do you know why they do so? Try to find out. shedding of leaves leaves changing colours There are some trees where leaves are not in their normal form. For example, cactus plant. The leaves of cactus are reduced to spines. cactus plant with spines Connect the Dots Social Studies Fun Banyan tree is India’s national tree. It has a stem with branches. banyan tree Maths Fun You have learnt about different types of patterns. Create two patterns using different types of leaf prints. A Note to Parent Take your child to a nearby garden. Show him or her various types of plants and trees. Ask him or her to identify the different types of leaves and stems. 44

Lesson Uses of Animals 10 I Will Learn About r animal products. u trained animals. a people who depend on animals for their livelihood. h kindness towards animals. I Think Have you ever wondered where we get woollen clothes from? Or where does the milk that you drink every morning come from? I Remember We find many animals around us. Some of them are very useful. Animals give us food and other things that we can use. Let us see how animals are useful to us: 1) Some animals and birds provide food. Animals like cows, buffaloes and goats give milk. They are called milch animals. We use milk to drink and to prepare milk products/dairy products. Curd, butter, ghee and cheese are some milk products. 45

cow buffalo milk and milk products hen Birds like hens and ducks eggs meat give us eggs. The meat of various animals and birds is used as food. Some aquatic (water) animals like fish and prawns are also used as food. 2) We get honey from honeycombs. We use honey in food and as fish prawns honeycomb honey medicine. 3) Animals like sheep and rabbit give us wool. Wool is used to make woollen clothes. They protect us from the cold. sheep wool woollen clothes 4) We get leather from the skin of animals like cows, pigs, goats, sheep, alligators and kangaroos. Bags, purses and belts are made from leather. We get fur from the skin of some animals like minks, foxes and rabbits. Fur is also used to make purses and coats. leather from animal skin bags, purses, shoes, belts animal fur fur coat 46