Next Generation Science Level 1 - Textbook B

Science for the Next Generation

Science Gra d e On e

Textbook

B

The 5E Model – Guided Inquiry The Next Generation Science series is based on the Biological Sciences Curriculum Study (BSCS) 5E teaching and learning instructional model.

The 5E model is centered on the idea that students understand science concepts best by using prior knowledge to pose questions and find answers through guided inquiry.

This hands-on approach, integrated with engineering and design skills, has students learn science by doing science. Teachers guide the learning process and are able to assess student performance by evaluating student explanations and the application of newly acquired knowledge and skills.

Engage

The Engage phase of the 5E model provides students with the opportunity to demonstrate their prior knowledge and understanding of the topic or concept. Students are presented with an activity or question which serves to motivate and engage students as they begin the lesson. Teachers identify and correct any misconceptions and gather data from students which will guide informed teaching and learning.

Essential to stimulating and engaging students is the use of mixed media such as colorful photos, illustrations and diagrams found throughout the textbooks and activity books. Next Generation Science also includes extensive digital resources such as narrated videos, interactive lessons, virtual labs, slideshows and more.

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Explore

This phase encourages exploration of concepts and skills through handson activities and investigations. Students are encouraged to work together and apply various process skills while gaining concrete, shared learning experiences. These experiences provide a foundation for which students can refer to while building their knowledge of new concepts. This studentcentered phase comes before formal explanations and definitions of the concept are presented by the teacher.

Explain

This phase follows the exploration phase and is more teacher-directed.

Students are initially encouraged to draw on their learning experiences and demonstrate their understanding of the concept through explanations and discussion. After the students have had the opportunity to demonstrate their understanding of the concept, the teacher then introduces formal definitions and scientific explanations. The teacher also clarifies any misconceptions that may have emerged during the Explore phase.

Elaborate

In the Elaborate phase, students refine and consolidate their acquired knowledge and skills. Opportunities are provided for students to further apply their knowledge and skills to new situations in order to broaden and deepen their understanding of the concept. Students may conduct additional investigations, share information and ideas, or apply their knowledge and skills to other disciplines.

Evaluate

This final phase includes both formal and informal assessments. These can include concept maps, physical models, journals as well as more traditional forms of summative assessment such as quizzes or writing assessments.

Students are encouraged to review and reflect on their own learning, and on their newly acquired knowledge, understanding and skills.

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Next Generation Science Next Generation Science is based on the United States Next Generation Science Standards (NGSS). The series consists of full-color textbooks and full-color activity books for Grades K to 6.

Need and

Next Generation Science engages students with a highly visual presentation of the disciplinary core ideas in the textbooks and places an emphasis on applying scientific knowledge using NGSS practices through numerous scientific investigations. Next Generation Science sees engineering as an essential element of science education and as such is tightly integrated into both the textbooks and activity books.

Anima living food,

Some for fo anim both

The Next Generation Science textbooks include the following features:

Think Deeply Topic-related questions for group discussion aimed at deepening students’ understanding of the topic.

In the Field

Can you imagine what it would be like to travel into space? What would the Earth look like from space? How would it feel to walk on the moon?

12 as far as the In the past, astronauts have traveled moon. As science and technologies advance, we are looking to venture further into space. Maybe you will be the first astronaut to travel all the way to Mars!

A person that travels into space is called an astronaut. Astronauts spend many years studying and training. Astronauts help us to learn more about space and the objects in our solar system.

Engineer It! Goes beyond inquiry by encouraging students to design, model and build to engineer solutions to defined problems.

In the Field Inspirational sciencerelated professions to stir interest in sciencerelated careers.

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A Closer Look

105

104

A Closer Look Invokes enthusiasm in science by presenting interesting topics beyond the syllabus.

Chameleons

Chameleons are lizards that have spec ial body parts that help them to survive in the place they live.

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Amazing Fact!

Interesting facts to build interest and enthusiasm.

Did You Know?

Animals and people drink the water they need.

ds of Animals People

als and people are things. They need water and air.

e animals eat plants ood. Others eat other mals. Some animals eat plants and animals.

How do you get the things you need from day to day.

Try This!

Optional hands-on activities to be conducted in groups or at home.

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Science Words

roots stem leaves flowers fruits fur

Extra information to build students’ knowledge base of the current topic.

People and land animals breathe in the air around them. Some animals, like fish, are able to get the air they need from water.

2. Describe two ways roots help

feathers scales lungs gills respond

3. True or false. (a) The roots hold the seeds for the plant. (b) Leaves use water, air and sunlight to mak e food for the plant.

4. Copy and complete the Body Covering

Review

1. Use the words in the box fruit

roots

stem

leaves

table.

Animal 1

Hair or Fur

to label the picture.

Animal 2

Feathers

flower

(d)

(a)

a plant.

7. (e)

Describe how a wire fenc e is similar to the blackberry bush.

(c) They have a long, stick y 54 tong ue that they shoot out to catch food such as insec ts.

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Chameleons have curle d tails which help them to hold on to tree branches.

Some chameleons can change the color of their skin. This helps them to blend in with their surro undings and avoid being spotted by predators such as birds .

Review 45

Links students to the Next Generation Science Activity Book at the appropriate juncture.

Scales or Shell 5. Which body part do fish use to breathe in water?

6. Describe one way an animal can respond to changes in its surroundi ngs.

(b)

AB Activity

Topical questions at the end of each chapter for formative assessment.

Discussion Topic-related questions and situations for class discussion to build a deeper understanding of topics.

Science Words Lists the essential science vocabulary covered in each chapter.

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Contents Unit 6 – Forces and Motion Describing Motion What Is a Force?

What Forces Can Do Review

Unit 7 – Matter What Is Matter?

States of Matter Changing Matter Review

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2 4 8 14 18

20 22 28 36 40

Unit 8 – Sound What Is Sound?

Describing Sounds Making Sounds Review

Unit 9 – Light Light and Dark Sources of Light Using Light Light and Shadows Light and Materials Reflecting Light Review

42 44 48 56 66

70 72 76 80 88 94 100 104

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Science Skills

Scientists use special skills to learn about the world around them.

Let’s look at how you can use these skills so you can be a scientist too.

Observe You observe when you gather information about something using your senses. You can observe how something looks, feels, sounds, smells or tastes.

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What senses are the children using to observe?

You can use different tools to observe things closely.

You can use a hand lens, binoculars or a telescope.

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Compare You compare things when you observe and tell how things are similar or different.

How are the hen and chick similar? How are they different?

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Classify When you compare two or more things, you can classify them into groups based on ways they are similar.

How have the leaves been classified into groups?

Leaves in the Garden

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Measure You measure when you find the size or amount of something.

You can use tools to help you measure things. You can use a ruler to compare and measure length.

You can use a balance to compare and measure mass.

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Make a Model You can make a model to test or see how something works.

You can make a model by drawing a picture.

You can also make a model by using the things around you to make a smaller version of something to show how it works.

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Infer You infer when you make a guess about something based on what you know or what you observe.

What can you infer about the cause of the holes in the leaf?

What can you infer from observing the tracks in the sand?

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Communicate You communicate when you tell or show other people what you find out.

You can communicate by making charts, drawing pictures or writing about what you find out.

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Science Investigations Ask Questions

Before a science investigation, ask questions about what you would like to find out.

Make a Prediction A prediction is a guess about what you will observe before you make the observation.

What are some things you would like to find out about in science?

Will a plant grow better in sunshine or darkness?

What do plants need to live and grow?

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A plant will grow better in sunlight.

Plan and Carry Out an Investigation Make a plan with steps that others can follow.

List all the materials you will need.

Procedure

Materials

1. Measure the heights of the plants.

2. Put one plant near a window. Put the other plant in a dark cupboard.

3. Water and observe the plants every day for one week.

two plants

ruler spray bottle with water

Observe and Record Data Record the things you observe. You can write or draw the things you observe. You can use charts and tables.

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Analyze and Interpret Data You analyze when you look closely at recorded data.

You interpret when you understand and explain what the data means.

Make a Conclusion and Communicate Make a conclusion and communicate it to others.

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Science Safety

Follow these safety rules when carrying out investigations.

Wear safety gear.

Follow your teacher’s instructions.

Keep your workspace clean.

Be careful with sharp objects.

Wash your hands after every activity.

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Forces and Motion How can we describe the ways things move?

In this chapter you will ...

• describe the position and motion of objects.

• identify pushes and pulls.

• describe how forces affect motion.

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How are people moving in these pictures?

Go Online!

Access interactive content relating to this topic on the NGScience website. ngscience.com

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Describing Motion Position

How can you describe where the objects are in the room?

The place an object is located is called its position. We can use different words to describe the position of objects. We can use words like on, under, above, left and right.

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When we describe position, we often compare the position of one object to another.

Let’s compare the position of objects to the desk.

We can say the guitar is to the left of the desk. The lamp is on the desk. The chair is under the desk.

AB

Activity 6.1

Try This!

With a partner, take turns in describing the positions of objects in your classroom. See if your partner can name the objects.

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Motion Go Online!

Observe and describe things in motion on the NGScience website.

QuickCode: Y2C9

When something moves, its position changes. When an object is in the process of changing position, we say it is in motion.

We can describe motion in different ways.

When you bowl a bowling ball, it rolls in a straight line. On a swing, you move back and forth. On a see-saw, you move up and down.

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Things can move from side to side, in a circle or a zigzag pattern.

We can also use speed to describe motion. Speed is how fast or slow something moves.

Try This!

Go into your school playground. With a partner, describe the motion of the things you see.

Some things, like a snail, move slowly. Other things, like a motorcycle, move fast or quickly.

AB

Activity 6.2

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What Is a Force?

When something is in motion it is because a force has caused it to move.

A force is a push or a pull.

A push is when you press something away from you.

You use a push to jump into the air, throw a ball or catch it.

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Try This!

Make a list of your daily activities. Group the activities as pushes, pulls or both.

A pull is when you tug something closer to you. Like when you tug on a rope or drag a sled in the snow.

AB

Activity 6.3

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A Closer Look

Gravity Gravity is a force that pulls things down towards the Earth.

When you throw a ball into the air, the Earth’s gravity pulls it to the ground.

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When you jump on a trampoline, you don’t fly off into the air.

You are pulled down by the Earth’s gravity.

The Earth’s gravity stops all the things on Earth from flying off into space!

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Different Forces Think Deeply Which requires the bigger force – moving a cart up a hill or down a hill? Explain your answer.

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The size of a force affects how an object moves. You can use a small force to move a small and light object – like the force used to push a pencil on your table.

You need a bigger force to move a larger and heavier object. Like the force used to slide a cupboard along a floor.

Big forces can also move things faster and further than smaller forces.

Compare the effect of different sized forces when playing golf. What does a small force do to the golf ball? What does a big force do?

AB

Activity 6.4

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Talk about the ways in which forces make a ball move during a game of tennis.

What Forces Can Do

When the boy uses a push to hit the tennis ball, it will start moving.

A force can start an object moving.

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The girl uses a push to catch the ball. The ball stops moving.

A force can stop a moving object.

Try This!

Roll a toy car down a ramp. How can you use force to stop the moving car?

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Go Online!

Observe how forces affect objects on the NGScience website.

QuickCode: E2W2

The girl applies forces from different directions as she bounces the ball. The ball moves in different directions.

A force can change the direction of a moving object.

What are some ways a force can change the direction of an object?

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A push can cause the swing to move faster. A pull can make the swing slow down.

A force can speed up or slow down a moving object.

AB

Engineer It! Design and build a pinball machine for a table tennis ball. Use the machine to show the different ways forces can affect the motion of the ball.

Activity 6.5

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Science Words

position motion speed force

push pull gravity

Review

1. What is a force?

2. List two examples of when you use a push.

3. List two examples of when you use a pull.

4. Which describes the location of an object? (a) motion (b) speed (c) position 5. Which describes an object in the process of changing position? (a) motion (b) speed (c) force

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6. Which describes how fast or slow an object moves? (a) position (b) speed (c) force 7. True or false. (a) Big forces can cause objects to move further and faster than small forces. (b) You need small forces to move heavy objects.

8. Use the words in the box to complete the sentences. moving stop direction slow down (a) A force can

a moving object.

(b) A force can start an object (c) A force can change the moving object.

. of a

(d) A force can cause an object to speed up or

.

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7

Matter

In this chapter you will ...

• describe the properties of matter.

• identify and describe solids, liquids and gases.

• describe how matter can be changed.

• describe how heat can change matter.

What is matter? How can we describe and sort matter?

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What are some ways matter can change?

Go Online!

Access interactive content relating to this topic on the NGScience website. ngscience.com

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What Is Matter?

Matter is what all things are made of. All of the objects in your classroom are matter.

Water and air are matter too.

Even you are matter.

What different kinds of matter can you see in the picture?

AB

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Activity 7.1

All matter has mass and takes up space.

Mass is the amount of matter in an object. We can compare the mass of different matter using a balance.

The ball has more mass than the toy elephant.

What matter is in your classroom? How can you describe the matter?

Try This!

Use a balance to compare the mass of different objects in your classroom.

Order the objects from the most mass to the least mass.

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Describing Matter We can describe matter in different ways using our senses.

Try This!

Close your eyes.

Have a classmate hand you an object.

Use your sense of touch to describe the object. Can you guess what it is?

We can describe how matter looks by observing its color, shape and size.

We can also describe how matter feels. Matter can be rough or smooth. It can be hard or soft.

The towels are soft and blue. The bowling ball is smooth and hard.

AB

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Activity 7.2

What words can you use to describe these objects?

In small groups, describe the objects in your classroom. Compare your descriptions with other groups.

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Sorting Matter Try This!

Empty your pencil case onto your desk.

Sort the objects in different ways. Tell your classmates how they are sorted.

Go Online!

Watch how matter can be sorted on the NGScience website.

QuickCode: N4S6

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We can sort or group matter based on ways they are similar.

The shirts and candy have been sorted by color.

These toys have been sorted by how they feel – hard toys and soft toys.

AB

Activity 7.3

Sort the things around you.

Tell how you sorted them.

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States of Matter

Matter can be classified by its state or form. There are three states of matter – solids, liquids and gases.

Solids The objects on your desk are solids. Solids have a shape of their own. The amount of space a solid takes up does not change.

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The shape and amount of space taken up by a solid does not change when it is moved from one container to another.

When you move your pencils from your pencil case to your desk, the pencils do not change.

What are some solids in your classroom? How can you tell they are solids?

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Liquids Pour some water from a bottle into a glass. How does the water change?

Try This!

Pour water into containers of different shapes and sizes. Describe how the shape of the water changes.

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Water is matter in the liquid state.

Liquids do not have a shape of their own. Liquids flow to take the shape of the container they are in.

When water is poured from a bottle into a glass, it flows to take the shape of the glass.

Think Deeply Sand flows and changes shape when it moves between containers. Is sand a solid or liquid?

Milk, oil and dish soap are also liquids.

What are some other liquids? How can you tell they are liquids?

AB Activities 7.4 – 7.5

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Gases Did You Know?

Air is a mixture of different gases. The main gases are called nitrogen and oxygen.

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What happens to a balloon when you blow air into it?

Air is a gas. A gas is a state of matter that does not have a set shape or size. A gas spreads out to fill the container it is in.

When you blow air into a balloon, the balloon changes shape and gets bigger as the air spreads out.

Discuss what happens to the air in a balloon when the balloon bursts.

AB

Go Online!

Explore the different states of matter on the NGScience website.

QuickCode: H1W3

Activities 7.6 – 7.7

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A Closer Look

Changing States of Matter Ice is water in a solid state. When ice is heated, it melts and becomes liquid water. If water is heated, it also changes state – it evaporates into a gas called water vapor.

What happens when water vapor is cooled?

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When water vapor cools, it changes back into liquid water.

This process is called condensation.

When the liquid water is cooled, it will freeze and change to solid ice.

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Changing Matter Reversible Changes

We can change matter in many ways. We change modeling clay when we use pushes, pulls and twists to change its shape.

We can also change the modeling clay back to its original shape.

A change to matter that can be changed back is called a reversible change.

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Heat can change matter too. When heat is added to a solid such as ice, it melts into water. When something melts, it changes from a solid to a liquid.

When water is cooled, it freezes into solid ice again.

When something freezes, it changes from a liquid to a solid.

Is melting butter a reversible change? How could you find out?

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Irreversible Changes Go Online!

Discover more about changes to matter on the NGScience website.

QuickCode: U8L5

Think Deeply What change takes place when you make orange juice? Is the change reversible or irreversible? Explain your answer.

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Sometimes matter is changed and cannot be changed back.

These changes are called irreversible changes.

Heat can cause irreversible changes. When you cook a raw egg, the egg changes. Cooling the egg will not change it back to a raw egg again.

Cutting a sheet of paper is an irreversible change.

The pieces of paper cannot be changed back into a sheet of paper.

Burning is also an irreversible change.

When you burn a piece of paper, it turns to ash. The ash cannot be changed back to a piece of paper.

AB

Activities 7.8 – 7.9

What are some other ways matter can change? Are the changes reversible or irreversible?

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Science Words

matter mass solid liquid gas

reversible change melt freeze irreversible change

Review

1.

True or false. (a) Matter is what all things are made of. (b) Mass is the amount of space matter takes up. (c) All matter has mass and takes up space.

2. Use two words to describe each object. (a) (b)

(c) (d)

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3. Use the words in the box to complete the sentences. gases liquids solids (a) Water and milk are examples of

.

(b)

have a shape of their own.

(c) they are in.

spread out to fill the container

4. What happens to solid matter when it is heated?

5. What happens to liquid matter when it is cooled?

6. Use the words in the box to complete the sentences. irreversible reversible (a) Freezing water is a (b) Cooking an egg is an (c) Melting chocolate is a

(d) Chopping wood is an

change. change. change. change.

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8

Sound

In this chapter you will ...

• describe how sounds are made.

• describe sounds around you.

• list ways people use sound.

What causes sounds?

How can you describe sounds?

Go Online!

Access interactive content relating to this topic on the NGScience website. ngscience.com

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Try This!

Stretch an elastic band over a plastic container. Pluck the elastic band to make different sounds. What do you observe?

How do people use sound?

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What Is Sound?

Try This!

Talk about the different sounds you hear from day to day. Classify them as sounds in nature and sounds made by people.

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Close your eyes and listen.

What sounds can you hear?

Sound is a form of energy we hear. We hear sounds using our ears and sense of hearing.

What Causes Sounds?

Strum the strings of a guitar. What do you hear? What do you see?

Touch the strings as they make a sound. What do you feel?

Sound is made when objects vibrate. Vibrate means to move back and forth very quickly.

AB

Try This!

Use different objects in your classroom to make sounds.

Describe the sounds to a partner. Talk about what makes the sound.

Activity 8.1

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Try This!

Make some sounds with different musical instruments.

What part of each instrument vibrates to make sound?

Describe how you are able to hear the sounds made.

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Sound and Vibrations When an object vibrates, it causes the air around it to vibrate too.

We hear sounds when the vibrating air reaches our ears.

AB

Activity 8.2

Sounds can also cause materials to vibrate. When the child talks into the tin can, it causes the air inside the tin can to vibrate. This causes the string to vibrate too.

Think Deeply Can sound travel through liquids and solids? Conduct an experiment to find out!

AB Activities 8.3 – 8.4

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Try This!

Make sounds by clapping your hands.

What do you do to make soft sounds?

What do you do to make loud sounds?

Describing Sounds Volume

How is the sound made when a kitten meows different from the sound of a lion’s roar?

Sounds can be loud or soft.

Volume is how loud or soft a sound is.

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The sound of an airplane taking off is a loud sound.

A whisper is a soft sound.

What are some other examples of loud and soft sounds?

AB

Activity 8.5

Engineer It! Design and make an instrument that can make loud and soft sounds. What do you do to change the volume of the sounds?

Go Online!

Compare the volume of different sounds on the NGScience website.

QuickCode: V3A6

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A Closer Look

Loud Animals!

You may think the roar of a lion is loud, but there are other animals that make even louder sounds!

Blue whales whistle to each other underwater. These whistles can be louder than a jet engine! The sounds can be heard underwater from over 800 km away!

Cicadas are the loudest insects. They make sound using a special part of their body that works like a drum!

Their sounds can be heard from over 2 km away!

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Kakapos are the loudest birds. They make a ‘booming’ sound that can be heard from 7 km away!

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Think Deeply Hit the different bars on a xylophone.

What can you infer about pitch and the length of the bars?

Pitch Sounds can be different in pitch.

Pitch is how high or low a sound is.

The chirp of a bird and the sound of a party whistle are high sounds.

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The sound of a moving truck is a low sound.

The sound of thunder during a storm is also a low sound.

What are some other examples of high and low sounds?

AB

Engineer It! Design and make an instrument that can make high and low sounds. What do you do to change the pitch of the sounds?

Activities 8.6 – 8.7 Go Online!

Compare the pitch of different sounds on the NGScience website.

QuickCode: E8H4

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What sounds do you hear from day to day?

Are the sounds loud or soft? Are they high or low?

Describe the sounds to a friend.

AB

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Activity 8.8

Describe the sounds made by the things on these pages.

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Making Sounds

Clap your hands. Blow a whistle. Bang on pots and pans. These are just some ways you can make sound.

What are some other ways you make sound? What vibrates to make the sound?

AB

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Activity 8.9

Using Your Voice Place two fingers on your throat.

Use your voice to make a loud sound. What do you feel?

In your throat are vocal cords.

The vocal cords vibrate and make sound.

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Musical Instruments We use many different types of musical instruments to make sound. Sound is made when part of the instrument vibrates.

Can you spot the way these instruments are the same?

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These instruments all have strings. They make sound when we cause the strings to vibrate.

What can you do to the strings on a guitar to change the sound that it makes? How does the sound change?

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Trumpets, flutes and trombones make sound when we blow into them. Sound is made when the air inside vibrates.

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Go Online!

Some instruments, such as drums cymbals and xylophones, make sound when we hit them.

Listen to the sounds of different musical instruments on the NGScience website.

Can you guess which instrument makes each sound?

QuickCode: R3U9

AB Activity 8.10

Engineer It! Design and build your very own musical instrument!

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Communication We use sound every day for communication.

We communicate using sound when we talk, laugh or cry.

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When you hear the school bell ring in the afternoon, you know it’s time to go home.

Bells, whistles, horns and sirens are other ways we use sound for communication.

AB

Engineer It! Can you communicate using sounds without using your voice?

Design and build a device that uses sound to communicate with a friend.

Activity 8.11

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Education Go Online!

Listen and guess the secret sounds on the NGScience website.

QuickCode: Q6Y8

We use sound to learn about the world around us.

At school, you use sound to listen to your teacher. You use sound to answer and ask questions.

Talk about the different ways you use sound at school.

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Entertainment We use sound to have fun!

You use sound when you listen and dance to your favorite music.

You use sound when you watch television or play video games.

AB

Activity 8.12

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Science Words

sound vibrate volume loud

soft pitch high low

Review

1. True or false. (a) Sound is a form of energy we hear. (b) Sound is made when objects vibrate. (c) Sound cannot travel through the air.

2. Which sense do you use to observe sounds? (a) Taste (b) Smell (c) Sight (d) Hearing 3. Choose a word to complete each sentence. pitch volume (a)

is how loud or soft a sound is.

(b)

is how high or low a sound is.

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4. Write two words to describe the sound made by the meow of a kitten.

(a)

(b)

5. Write two words to describe the sound made by the roar of a bear.

(a)

(b)

6. List two ways you make sound.

(a) (b) 7. List two ways you use sound. (a)

(b) 67

In the Field

Sound travels very fast. If you become a fighter pilot, you could travel faster than the speed of sound!

To become a fighter pilot takes a lot of hard work and study. Pilots must learn a lot of science and mathematics before they can fly.

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Fighter jets can fly very fast and are very loud.

Some jets can move faster than the sound made by the jets!

When a fighter jet travels faster than sound, it makes a very loud sound – much like thunder.

This sound is called a sonic boom!

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9

Light

Why do we need light?

What happens if there is no light?

How do we use light?

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In this chapter you will ...

• understand how light helps us to see.

• describe and list sources of light.

• list some ways people use light.

• understand how shadows form.

Try This!

Are you able to see an object in darkness? Conduct an investigation to find out!

Go Online!

Access interactive content relating to this topic on the NGScience website. ngscience.com

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Light and Dark Light

Did You Know?

The light from the Sun is very helpful, but it can also be harmful. It can damage your eyes and skin.

Never look directly at the Sun and wear sunscreen on sunny days.

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Go outside and look around you.

What things can you see?

You can see the things around you because of light. Light is a form of energy.

During the day, the light from the Sun helps you to see.

At night, there is no light from the Sun. People use light bulbs, flashlights, headlights and fire to see the things around them.

What things do people use to help them see at night?

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Dark Try This!

Can a camera take photographs in darkness? Conduct an experiment to find out!

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In the dark there is no light. You are in darkness.

In darkness you cannot see the things around you. To see things in the dark you need to use light.

What things can you use to help you see when there is darkness?

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Sources of Light

Did You Know?

The moon is not a source of light. It does not produce light of its own. You can see the moon because the Sun shines on it.

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The Sun, lamps and fire are things that give off light of their own.

Something that gives off light of its own is called a source of light.

Natural Sources of Light Some sources of light are found in nature. They are not made by people. They are called natural sources of light.

The Sun, stars, fire and lightning are natural sources of light.

Go Online!

Some living things, such as fireflies, can give out light of their own.

This amazing ability is called bioluminescence.

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Artificial Sources of Light Go Online!

Discover more about artificial sources of light on the NGScience website.

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Many sources of light are made by people. They are called artificial sources of light.

Electrical lights are artificial sources of light. They light up our cities, streets and homes at night.

Televisions, computer monitors and phone screens give out light.

They are also artificial sources of light.

AB

Activities 9.1 – 9.2 Think Deeply Are fireworks natural or artificial sources of light? Discuss with your friends.

What are some other artificial sources of light?

How are they used?

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Using Light

Go Online!

Watch a video on the ways we use light on the NGScience website.

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During the day, we use the light from the Sun to help us see.

How are the people using light? What is the source of light?

At night, we use lights to light up our cities, streets and homes.

What will happen if the lights in the stadium are switched off?

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Headlights produce light to help drivers see at night.

Lights also help us to see underwater and underground.

How are the people using light?

What is the source of light?

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We use light for entertainment and education.

Fireworks light up the sky on New Year’s Eve. Theater lights light up the stage during a concert.

Amazing Fact!

A laser is a tool that lets out a powerful beam of light. We can use lasers to cut metal and other materials!

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You use lights for entertainment and education when you watch television, play video games or use a computer.

Can you point to the source of light in these pictures?

AB Activities 9.3 – 9.4

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We use light for communication.

The flashing lights and sirens let you know there is an emergency.

Lights can keep you safe from danger. They can tell you when a train is approaching or when it is safe to cross the road.

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Cyclists use lights at night to let cars and people know where they are.

Brake lights on cars let other drivers know that the car is slowing down or stopping.

Talk about the different ways lights are used for communication.

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Engineer It!

Lights are used on signs so they stand out and we can see them when it is dark.

AB

Design and build a device that can send messages over a distance using light!

Activity 9.5

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Engineer It! Use what you know about light and shadows to build a shadow puppet show stage. Put on a shadow puppet show for your friends.

Light and Shadows How Are Shadows Formed?

Place your hand near a wall and shine a flashlight on your hand.

What do you see?

When an object blocks light, a shadow is formed. The dark area you see when you shine a flashlight on your hand is a shadow.

What do you notice about the shape of the girl’s hand and the shadow?

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You see shadows during the day when objects block the light from the Sun. You see shadows at night when light is blocked from other sources of light.

AB

Activity 9.6

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Shadow Shape and Size Look at the shadows on this page.

What object is making each shadow? How do you know?

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Light travels in waves. When an object blocks

The shape of a shadow is always similar in shape to the object blocking the light.

What can you do to change the size of a shadow?

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Changing Shadows Place an object in front of a flashlight and observe the shadow. Move the flashlight closer to the object. What happens to the size of the shadow?

Shadows can change size. When light moves closer to an object, the shadow gets larger.

When light moves further from the object, the shadow gets smaller.

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How does your shadow change at different times of the day?

Shadows can also change in shape. When the flashlight moves higher, the shadow gets shorter.

When the flashlight moves lower, the shadow gets longer.

AB

Activity 9.7

Try This!

Find a clear area outside and observe your shadow at different times of the day.

How does the shape of your shadow change? What causes the change?

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Light and Materials Think Deeply What material is each bowl made of ? How are the materials different in the amount of light they allow to pass through?

A material is what an object is made of.

Materials can be different in the amount of light that can pass through them.

Why are you able to see the block in the glass container clearly?

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Opaque Materials A material that blocks all light is opaque.

We cannot see through opaque materials.

When light hits an opaque object, a shadow is made.

Why can’t you see out of the window?

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Translucent Materials A material that allows only some light to pass through is translucent.

We cannot see clearly through translucent materials.

When light hits a translucent object, a light shadow is made.

Why are you able to see through the curtain?

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Transparent Materials

A material that allows light to pass through is transparent.

We can see through transparent materials.

When light hits an object made of a transparent material, no shadow is made.

Why are you able to see the mountain clearly?

AB

Activities 9.8 – 9.9

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Knowing how light can pass through materials allows us to choose materials that are useful and safe for how they are used.

A car windscreen is made of transparent glass. This allows the driver to see clearly and drive safely.

What are some objects that are useful because they are opaque?

The boy’s hat is opaque.

This blocks the sunlight from reaching his face.

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What are some objects that are useful because they are transparent?

How is the amount of light passing through these objects useful?

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Reflecting Light You are able to see a source of light when light travels from the source to your eyes.

Many things around you are not sources of light. How are you able to see them?

The moon is not a source of light. The moon appears bright because it reflects the light from the Sun. Reflect means to bounce off.

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You are able to see the things around you when they reflect light.

Trace the path the light takes from the Sun to the girl’s eyes.

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Some shiny, smooth objects reflect light in a way that allows you to see reflections.

The girl is able to see her reflection because the mirror reflects light to her eyes.

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A newly washed car and the still water in a pond have a smooth and shiny surface. They reflect a lot of light.

Dull and rough surfaces do not reflect light well.

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Science Words

light dark source of light shadow

material opaque translucent transparent

Review

1. True or false. (a) Light is a form of energy. (b) We can see in darkness. (c) The moon is a source of light.

2. List two natural sources of light. (a)

(b)

3. List two artificial sources of light. (a)

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(b)

4. Describe two ways you use light during the day.

5. Describe two ways you use light at night.

6. True or false. (a) A shadow is formed when light passes through an object. (b) A shadow is formed when an object blocks light.

7. Use each word to label the objects. opaque translucent transparent (a)

(b)

(c)

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© Blue Ring Media Pty Ltd ACN 161 590 496 2013 - 2021.

This publication would not have been possible without the tireless effort of our production team.

Special thanks to: Matthew Cole, Daniel Cole, Wang Hui Guan Joseph Anderson, Halle Taylor-Pritchard, Sophie Taylor-Pritchard, Tejal Thakur Varasinun Mathanattapat, Kanungnit Pookwanmuang, Saijit Lueangsrisuk Original Illustrations: Natchanuch Nakapat, graphicsRF, Blue Ring Media and Interact Images Royalty-free images: Shutterstock, Adobe Stock