Science for the Next Generation
Science K i n d erg a rt en Textbook
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The 5E Model – Guided Inquiry The Let’s Do 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. Let’s Do 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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Let’s Do Science Let’s Do 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. Let’s Do 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. Let’s Do Science sees engineering as an essential element of science education and as such is tightly integrated into both the textbooks and activity books. The Let’s Do Science textbooks include the following features:
Think Deeply Topic-related questions for group discussion aimed at deepening students’ understanding of the topic.
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 Invokes enthusiasm in science by presenting interesting topics beyond the syllabus.
Amazing Fact! Interesting facts to build interest and enthusiasm.
Did You Know? Extra information to build students’ knowledge base of the current topic.
Try This! Optional hands-on activities to be conducted in groups or at home.
AB Activity Links students to the Let’s Do Science Activity Book at the appropriate juncture.
Discussion Topic-related questions and situations for class discussion to build a deeper understanding of topics.
Review Topical questions at the end of each chapter for formative assessment.
Science Words Lists the essential science vocabulary covered in each chapter.
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Contents Unit 6 – Changes to the Environment 2 Natural Changes Human Changes Caring for the Environment Review
4 10 18 26
Unit 7 – The Earth and the Sun 30 Our Sun Earth and the Moon Review
32 42 44
Unit 8 – Weather and Seasons 48 Daily Weather Around the World Seasons Weather Forecasts Severe Weather Review vi
50 55 56 62 64 78
Unit 9 – Forces and Motion 82 What Is a Force? Using Forces How Things Move Forces in Nature Force and Movement Review
84 92 94 98 100 112
Unit 10 – Matter 116 Describing Matter Grouping Matter Changing Matter Objects and Matter States of Matter Review
118 120 122 124 126 128
Unit 11 – Sound and Light 132 What Is Sound? What Is Light? Review
134 140 150
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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. Communicate your conclusion 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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Changes to the Environment
How do plants, animals and people change the environment?
In this chapter you will ... • understand and describe ways in which plants and animals can change the environment. • understand and describe ways in which people can change the environment. • list and describe ways in which we can reduce our impact on other living things and/or the environment.
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Go Online! Access interactive content relating to this topic on the NGScience website. ngscience.com
How can we reduce our impact on the environment? 3
Natural Changes Plant Changes Try This! Walk around your schoolyard. Can you spot ways in which plants are changing the environment? Draw pictures or make notes about what you observe.
Everything surrounding a living thing is its environment. Plants can cause changes to their environment. What are some ways plants can change the environment? Tree roots cause changes when they break apart concrete.
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As trees grow, they can block sunlight, making the environment darker. When a tree falls, it changes the environment too. AB
Activities 6.1 – 6.2
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Animal Changes What are some ways animals can change the environment? Animals can change their environment when they eat the plants around them.
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A woodpecker causes changes when it uses its strong beak to break open tree trunks in search of insects. Beavers cause changes to the environment when they cut down trees and build dams.
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Squirrels change their environment by collecting nuts from trees. They dig holes to bury the nuts.
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Animals can also change the environment when they build their homes. Rabbits, mice and prairie dogs dig burrows. Digging burrows changes the environment. AB
Activities 6.3 – 6.4
Think Deeply Meerkats live in hot places. They dig burrows for protection against other animals. How else do burrows help meerkats?
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Human Changes
People can change the environment when they get things they need from nature. Try This! Walk around your home or schoolyard. Tell or draw the way people have changed the environment.
Things we use and take from nature are called resources. Some resources we use are air, water, soil and wood. What are some ways people change the environment?
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People change the environment when they build roads and cities. The changes that people make to the environment can affect the plants and animals that live there.
Think Deeply What happens to plants and animals when people change their environment?
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Clearing Forests Forests are cleared to make way for cities or farmland. Did You Know? The clearing of forests is called deforestation.
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Forests are also cleared for wood and other resources. Clearing forests causes a big change to the environment.
What happens to forest plants and animals when a forest is cleared? When forests are cleared by people, the plants that live there often die. Animals can also die or must move to new places. AB
Activity 6.5
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Changing Our Water Pollution occurs when people add harmful things to the environment. Harmful things added to our rivers, lakes and oceans cause water pollution.
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What are some ways people can cause water pollution? Water pollution changes the environment. It harms the living things that live there. Some living things may not be able to survive in the polluted water.
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Changing Our Land People cause land pollution when they add harmful things to the land. Littering and dumping wastes are types of land pollution.
How can we reduce land pollution? 16
Changing Our Air
Go Online!
Burning rubbish and smoke from cars and factories changes the air. These activities cause air pollution.
Learn more about the ways people can change the environment on the NGScience website. QuickCode: A7E8
Air pollution is harmful to living things, including people. AB
Activity 6.6
How can we reduce air pollution? 17
Caring for the Environment
Think Deeply How can you take your groceries home without using new plastic bags each time?
There are many ways that people can help the environment.
Reduce Reduce means to produce or use less. We can help the environment by reducing the amount of waste we produce. We can also reduce the amount of water and electricity we use.
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Reuse We can reduce waste by reusing things. Reuse means to use an old object again. These tires have been reused to make play equipment. AB
Activity 6.7
Engineer It! Take some old objects from home and reuse them to make something new.
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Recycle Try This! Set up a ‘recycling station’ in your classroom. See which class can recycle the most things.
Did You Know? You can also help protect the environment by buying things made from recycled materials.
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We can help the environment by recycling. Recycle means to make an old object into something new.
Almost all of the waste we produce can be recycled. We can recycle cans, bottles, paper and cardboard. How does reducing, reusing and recycling help the environment? AB
Activity 6.8
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Other Ways to Help the Environment Try This! Plan a clean-up day for a park or reserve near your school!
There are many ways we can help the environment. You can pick up trash.
Keep to paths and trails.
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Walk or ride a bicycle instead of using a car.
Turn off lights and taps when they are not being used. AB
Activity 6.9
Did You Know? Washing machines and dishwashers have settings that use less water.
What are some other ways we can care for the environment? 23
A Closer Look
Electric Cars One way we can reduce pollution and protect the environment is by switching to electric cars. Many cars are powered by burning gasoline. This produces smoke which causes air pollution. Electric cars are powered by batteries. They do not produce any smoke.
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Like a toy car, when the batteries in an electric car are flat, they can be recharged.
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Science Words
environment pollution water pollution land pollution
air pollution reduce reuse recycle
Review
1. Which best describes an environment? (a) A change to a place. (b) The living things in a place. (c) Everything surrounding a living thing. 2. Talk about two ways plants can change their environment. 3. Talk about two ways animals can change their environment. 4. Talk about what happens to living things when people harm the environment.
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5. Choose a word to describe each picture. land clearing air pollution water pollution land pollution (a) (b)
(c) (d)
6. Choose a word to describe each picture. recycle reuse reduce (a) (b)
(c)
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In the Field
If you like living things and the ocean, you might want to be a marine biologist! A marine biologist collects and analyzes data about the ocean and the living things that live there. 28
A marine biologist may work underwater, from a boat or in a science laboratory.
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The Earth and the Sun
In this chapter you will ... • be able to describe the Sun. • understand how the Sun affects the Earth. • understand the importance of the Sun to living things.
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How does the Sun cause changes on Earth? AB
Activity 7.1
Go Online! Access interactive content relating to this topic on the NGScience website. ngscience.com
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Our Sun
The Sun is a large ball of hot, glowing gas. The Sun is a star. There are many stars in space. The Sun is the closest star to Earth.
Sun
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Earth is the planet we live on.
Earth
How does the Sun affect the Earth?
Amazing Fact! The Sun is so big that more than one million Earths could fit inside it!
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Did You Know? Never look at the Sun directly. The light is so bright that it can damage your eyes.
During the day, the Sun is the largest and brightest object in the sky. The Sun gives out light. It lights up the Earth and helps us to see.
What would daily life be like without the light from the Sun? 34
The Sun also gives out heat. It helps to keep all living things on Earth warm.
How does the heat from the Sun help living things? 35
The Heat from the Sun
The heat from the Sun warms all parts of the Earth.
Try This! Using a thermometer, design an experiment to show how sunlight warms water.
The heat from the Sun warms our oceans. 36
The heat from the Sun warms the land and the air. The heat from the Sun keeps living things warm.
Engineer It! You have learned that ice melts faster in sunlight. What could you do to slow the melting of ice in sunlight?
Try This!
AB
Activities 7.2 – 7.3
The heat from the Sun also warms the non-living things around us.
Walk around your schoolyard and use your sense of touch to observe the temperature of things in sunlight and things in the shade. What do you notice?
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The Light from the Sun The light from the Sun is called sunlight.
Plants use the energy from sunlight to make the food they need to live and grow. Without the light from the Sun, there would be no plants on Earth.
Why is sunlight important for living things? 38
Animals need sunlight. Many animals get the food they need by eating plants. Sunlight also helps many animals to see during the day. Engineer It! Think of your favorite pet. Design and build a shelter that will provide your pet with shade and keep it cool on a hot, sunny day.
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Did You Know? Sunlight can be damaging to your skin. Always wear Sun protection when outdoors on a sunny day.
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People need sunlight too. Sunlight helps us to see. How do you use sunlight during the day?
Without sunlight, we would not be able to get the food we need from plants and animals.
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Earth and the Moon
Go Online! Discover more about the Earth and the moon on the NGScience website. QuickCode: R6N9
There are many planets in space. Earth is the planet we live on. It is the only planet that is known to have living things.
Why does the Earth look blue from space? 42
Try This!
What things can you see in the sky at night?
Observe the moon in the night sky at different times of the month. What changes or patterns do you see?
If you look into the sky on a clear night, you might see the Earth’s moon.
Amazing Fact!
The moon appears bright in the night sky when the light from the Sun shines on it.
Things are always moving in space. The Earth moves in a pattern around the Sun. The moon moves in a pattern around the Earth!
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Science Words
Sun star Earth
planet heat light
Review
1. What is the Sun? (a) A star. (b) The Earth. (c) A planet. 2. True or false. (a) The Sun is much bigger than the Earth. (b) The Sun is the planet we live on. 3. List two things that the Sun gives out. 4. How does the light from the Sun affect the Earth? (a) It keeps the Earth cool. (b) It warms the Earth. (c) It lights up the sky.
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5. How does the heat from the Sun affect the Earth? (a) It keeps the Earth cool. (b) It warms the Earth. (c) It lights up the sky. 6. How does the Sun help plants? (a) Plants use its light to make food. (b) It keeps plants cool. (c) It helps plants to see during the day. 7. Describe two ways the Sun helps people and animals.
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In the Field
A climatologist is a specialized scientist. Climatologists collect and study data from ice, soil, water and plants. They look for patterns about how the temperature of Earth is changing.
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Climatologists look at how long-term changes in temperature affect the environment and living things.
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Weather and Seasons How does the weather change from day to day?
In this chapter you will ... • make observations about the weather, describe weather and weather patterns. • list and describe the four seasons. • describe severe weather. • understand the importance of weather forecasting to prepare for, and respond to, severe weather.
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Go Online! Access interactive content relating to this topic on the NGScience website. ngscience.com
How does the weather change throughout the year? 49
Daily Weather
Try This! Go outside. Write three words to describe the weather.
Go Online! Watch a video about different types of weather on the NGScience website. QuickCode: E6Z3
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Weather is what the air and the sky are like outside. The weather can change from day to day. Weather can affect the things we wear and how we act.
Hot and Cold Sometimes the air outside is hot. What activities do you do when the weather is hot?
Other times the air outside is cold. What activities do you do when the weather is cold?
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In the Sky
Sometimes the Sun shines bright in the sky during the day. The weather is sunny.
Try This! Go outside and observe the sky. Draw the clouds you see. Do not look at the Sun. The light from the Sun can damage your eyes.
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Sometimes clouds cover the sky and we cannot see the Sun. The weather is cloudy.
Engineer It!
Sometimes rain falls from the clouds.
On other days there may be a lot of wind. AB
Activities 8.1 – 8.3
It’s a rainy day and you forgot your umbrella. Design something to protect yourself from the rain. Draw a model to show your design.
Amazing Fact! Wind doesn’t make sound until it blows against an object!
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When the weather is very cold, snow may fall from the sky. How does weather affect the clothes you wear?
Try This! Make a weather journal. Draw a picture and write a few words to describe the weather each day for a week.
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AB
Activities 8.4 – 8.6
Around the World
The weather can be different in different places. In some places, the weather is hot every day. Other places are very cold all year long.
Amazing Fact! The coldest recorded temperature on Earth was measured in Antarctica. The temperature was −89 °C (–128 °F).
Some places get lots of rain. In other places it may not rain all year.
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Seasons
Go Online! Watch a video about the four seasons on the NGScience website. QuickCode: X7T4
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Have you ever noticed that the weather changes throughout the year? Some months may be hotter than others. In some months it may rain more often. These changes are called seasons. In many parts of the world, there are four seasons – spring, summer, fall and winter.
As the weather changes in each season, the plants change too. Animal behaviors also change.
How do seasons change the environment? 57
Spring
During spring, the weather is warm. Plants begin to grow. Animals have babies.
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Summer
Summer comes after spring. It is the hottest season. There are many sunny days.
Amazing Fact! In summer, there are more hours of daylight than in other seasons.
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Fall
Fall comes after summer. The weather begins to get cooler. Plant leaves change color and fall to the ground.
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Winter
Winter comes after fall. It is the coldest season. Many plants do not have leaves or flowers. Some animals move to warmer places during winter. AB
Activities 8.7 – 8.8
In what ways is winter different from summer? 61
Weather Forecasts
Scientists use tools to observe how weather moves in patterns. This allows them to know what the weather will be like in the coming days.
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How are weather forecasts useful to people?
Weather forecasts help people plan for outdoor activities. They can tell us when the weather will be hot or cold. They can tell us when it will rain. Weather forecasts can also let us know of severe weather.
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Severe Weather
At times the weather can be dangerous. It can harm people, plants and animals.
Thunderstorms Go Online! Watch a video about different kinds of severe weather on the NGScience website. QuickCode: S6L8
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During a thunderstorm, there are strong winds and heavy rain. Lightning can light up the sky. The lightning makes a sound called thunder.
The strong winds, heavy rain and lightning during a thunderstorm can be dangerous to people. It is important to stay inside during a thunderstorm.
Think Deeply A thunderstorm is also called an electrical storm. Why is this so?
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Hurricanes A hurricane is a very large storm that starts in the ocean and moves on to land. Hurricanes have very strong winds and heavy rain.
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Hurricanes can cause floods and damage property. It is important to know when a hurricane or thunderstorm is coming so we can stay safe.
What can you do to stay safe during a hurricane? 67
Earthquakes and Tsunamis An earthquake is a shaking of the ground caused when parts of the Earth rub together.
Most earthquakes are small and do not cause many changes. Sometimes, earthquakes can be big and cause damage to buildings and roads.
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An earthquake in the ocean can cause a tsunami. A tsunami is a large, powerful wave that can move from the ocean to land. Tsunamis can cause floods and damage homes and buildings.
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Other Extreme Weather
Different places on Earth have different types of extreme weather. In some places there may be lots of rain for many days causing a flood.
In other places it may not rain for many months causing a drought. During a drought there may not be enough water for living things.
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Sometimes the weather may get much hotter than usual. This weather pattern, called a heatwave, can be harmful to people and animals.
During a winter storm it may snow for many days. It may not be safe to go outdoors. AB
Activity 8.9
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Severe Weather Warnings Severe weather can be dangerous. Weather patterns help scientists predict severe weather before it happens. How is knowing about severe weather before it happens useful?
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Severe weather alerts tell people about severe weather. Alerts can be sent to people through televisions, the radio or mobile phones. AB
Activity 8.10
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Severe Weather Safety
Did You Know? Your body loses water quickly during a heatwave. You should find ways to stay cool and drink lots of water.
Ways to be prepared and stay safe during severe weather: • Cover doors and windows. • Find shelter and stay indoors. • Have food, water and a flashlight nearby.
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Go Online! Learn other ways to plan for severe weather on the NGScience website. QuickCode: C5J4
Try This!
• Go to cooling centers during heat waves. • Evacuate coastal areas before a hurricane or tsunami.
Make a severe weather safety poster for your home. Stick it in a place for your family to see.
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A Closer Look
Tornadoes In some parts of the world, tornadoes can form during severe thunderstorms. Tornadoes are long tubes of air that reach from the ground to the clouds. The air spins very fast and can cause a lot of damage. Tornadoes can destroy homes, cars and landscapes.
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In places where tornadoes occur, special buildings called tornado shelters are built. People can safely stay inside these shelters as the tornado moves through their city.
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Science Words
weather hot cold sunny clouds cloudy
rain wind snow seasons spring summer
fall winter thunderstorm lightning thunder hurricane
Review
1. What is weather? (a) A hot or cold day. (b) What the air and the sky are like outside. (c) A thunderstorm. 2. True or false. (a) Weather can change from day to day. (b) Weather can affect the clothes we wear. 3. List four words you can use to describe weather.
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4. Choose a word to describe each picture. summer winter fall spring (a) (b)
(c) (d)
5. Which is the hottest season? (a) winter (b) summer (c) fall (d) spring 6. Which season comes after summer? (a) winter (b) summer (c) fall (d) spring 7. List four types of severe weather.
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In the Field
A meteorologist is a scientist that uses special equipment and tools to study weather and weather patterns. Meteorologists are able to predict storms and hurricanes and tell what the weather will be like in the coming days.
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Meteorologists are very helpful. They share the things they observe and predict. This helps us prepare for weather each day. They also help us prepare for severe weather events.
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Forces and Motion
What are pushes and pulls? What can pushes and pulls do?
In this chapter you will ... • describe force. • distinguish between pushes and pulls. • identify pushes and pulls in everyday life. • identify forces in nature. • discover how forces can affect motion.
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Go Online! Access interactive content relating to this topic on the NGScience website. ngscience.com
How do forces affect motion? AB
Activity 9.1
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What Is a Force?
What things can you see in the pictures? How are the things moving? What causes them to move?
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The things you see are moving because of forces. A force is a push or a pull. Which are pushes? Which are pulls?
Try This! Walk around your schoolyard at lunch time. What things are moving? What causes them to move?
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A push is when you press something away from you. Ethan is using a push force.
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A pull is when you tug something closer to you. Jordan is using a pull force.
What happens to the car when it is pushed and pulled?
Try This! Tie a piece of string to a toy car. Pull on the string. Push the car. What do you observe?
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You use a push when you throw, hit or kick a ball.
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You use a push when you jump in the air. What are some other ways we use pushes?
How is the girl using a push force? 89
You use a pull when you drag a sled, climb a rope or rake some leaves. What is causing the sled to move? AB
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Activity 9.2
Think Deeply When you pick up your school bag, do you use a push or a pull? Go Online! Watch a video on pushes and pulls on the NGScience website. QuickCode: Z4Z6
What are some other times you use a pull? 91
Using Forces Every day you use forces to make things move in different ways. You use forces when you: • Brush your teeth. • Get dressed. • Open or close a door. • Write, draw or paint. • Pick up your schoolbag. • Exercise and play.
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What forces do you use when you ride a bicycle? What are some other ways you use forces in daily life? Do you use pushes, pulls or both? What do the forces do? AB
Activity 9.3
Try This! Act out sweeping with a broom with a partner. How does the broom move? Do you use pushes, pulls or both?
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How Things Move
Go Online! Watch a video showing how things move on the NGScience website. QuickCode: K8J8
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Forces make things move in different ways. When you bowl a bowling ball, it moves in a straight line. On a swing, you move back and forth. On a see-saw, you move up and down.
A carousel moves round and round. Things can move slow or fast. You move slowly when you walk. You move faster when you run. What other ways can you tell how things move? AB
Activities 9.4 – 9.6
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Think of all the ways forces move things in a playground. Which are pushes? Which are pulls?
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Forces in Nature
Forces in nature cause things to move. Wind is causing the sailboats to move.
Engineer It! Design and build your own sailboat that will move in water!
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Moving water pushes the kayak down the river. It pushes a surfer along a wave. Wind and moving water are forces in nature.
Amazing Fact! People can use the force of moving water and wind to make electricity!
What causes the windmill and leaves to move? AB
Activity 9.7
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Force and Movement The movement of an object is called its motion.
Forces can start, stop and change the motion of an object.
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How does the movement of a ball change during a game of tennis?
Go Online! Watch sports in action on the NGScience website. Describe how forces affect motion. QuickCode: U4P4
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Start and Stop
When you pull on the string of a balloon, you start it moving.
Amazing Fact! During a strongman competition, competitors use pushes and pulls to move a truck!
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When you use a push to throw a ball, it starts moving. A force can start an object moving. What force does the girl use to start moving on her scooter?
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The push force of a kick causes the football to start moving. When the goalkeeper catches the ball, he uses a push force to stop the moving ball. A force can stop a moving object.
In what other sports do you use a push force to stop a ball?
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What are some examples where a force is used to stop a moving object? Are the forces pushes or pulls? Engineer It! Find a sloped surface in your school. Roll a ball down the slope. With your friends, design something to stop the ball from moving.
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Fast and Slow
Take a toy car and give it a soft push. Try again using a hard push. What do you notice about the motion of the car? Forces can make things move at different speeds. When you use a soft push, the toy car moves slowly. When you use a hard push, the toy car moves faster.
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How do hard and soft pushes affect the way a cyclist moves?
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Changing Direction
An object moves in the direction it is pushed or pulled. When you throw a basketball, it moves in the direction you push it. You can change the direction the ball is moving by pushing it in a different direction. Forces can change the direction of a moving object.
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How does the direction of a ball change during a basketball game?
Go Online! Go to the NGScience website to watch the ways forces make a ball move during a game of basketball. QuickCode: U3S4
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Speed Up and Slow Down When the father pushes the boy, he will go faster.
A force can cause a moving object to speed up.
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When the cyclist squeezes the brakes, the bicycle slows down. A force can cause a moving object to slow down. AB
Activities 9.8 – 9.9 Go Online! Observe the different ways forces make things move on the NGScience website. QuickCode: S7C8
Engineer It! As a class, design and build a maze for a ball. Think about how forces will guide the ball through the maze.
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Science Words
force push pull motion
change direction speed up slow down
Review
1. What is a force? 2. True or false. (a) A pull is when you press something away. (b) A pull is when you tug something closer. 3. Choose a word to label the type of force. pull push (a)
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(b)
4. Tell two ways you use a push force. 5. Tell two ways you use a pull force. 6. Name an activity that uses pushes and pulls. 7. List two forces in nature. 8. What will happen when Blake pedals harder?
(a) He will slow down. (b) He will stop. (c) He will speed up. 9. What will happen when Halle hits the ball?
(a) The ball will stop. (b) The ball will change direction. (c) The ball will start moving. 113
In the Field
How much force does it take to push a spacecraft into space? This is one of the challenges of an aerospace engineer!
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An aerospace engineer researches, designs and tests rockets that carry objects into space.
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Matter
In this chapter you will ... • describe and group the things around you. • describe how matter can change. • list the three states of matter and list examples of each.
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How can we observe and describe the world around us? AB
Activity 10.1
Go Online! Access interactive content relating to this topic on the NGScience website. ngscience.com
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Describing Matter
The air you breathe, the water you drink and the toys you play with are all matter. Matter is what all things are made of. Even you are matter. We can describe matter in many ways. What are some examples of matter in your classroom?
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We can describe matter by how it looks. We can describe the size, color and shape of matter. We can also describe matter by how it feels.
Try This! At home, use your senses of touch and sight to describe your favorite toy.
How can you describe the matter in the bedroom? AB
Activity 10.2
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Grouping Matter
We can group the objects around us by the ways they are the same. We can group things by color, shape, size or how they feel.
The objects are grouped by color.
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We can also group things by their use or function.
The objects are grouped by how they are used.
AB
Activities 10.3 – 10.4
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Changing Matter Matter can change.
You can push, pull and twist clay to change its shape. You can fold and cut paper into different shapes and sizes. What are some other ways matter can change?
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When you put water in a freezer, it changes into ice. Ice changes to water when it melts. AB
Activity 10.5
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Objects and Matter
We use objects in different ways. Different objects have different functions. The matter we use to make an object must match its use. How is the matter in each tool matched to its use?
The table is hard and strong. The rug is soft and strong. 124
Engineer It! Design and build a bridge to move a toy car from one desk to another.
Glass windows allow us to see outside.
AB
Activity 10.6
How does matter help these objects to function? 125
States of Matter
Think Deeply What happens to an ice cream on a hot day? Why does this occur?
There are three states of matter – solid, liquid and gas. A solid is matter that keeps its shape. The park bench is solid matter. A liquid is matter that flows and changes shape. The water in the lake is liquid matter.
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Try This!
A gas is matter that floats freely. A gas spreads out. The air we breathe is a gas. AB
Blow air into a balloon. What happens to the size and shape of the balloon?
Activity 10.7
Go Online! Watch a video about the different states of matter on the NGScience website. QuickCode: Q7U1
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Science Words
matter solid
liquid gas
Review
1. True or false. (a) Matter is what all things are made of. (b) People are not matter. 2. List three things around you that are matter. 3. Use two words to describe each object. (a)
(b)
(c)
(d)
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4. What makes each object suited to its use? (a)
(b)
(c)
5. List the three states of matter. 6. Give one example of each state of matter.
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In the Field
A material is what an object is made of. A materials scientist is a special type of scientist that invents new types of materials.
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They invent materials that can be lighter, stronger or harder than other materials.
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11
Sound and Light
How do people use light? Where does the light come from?
In this chapter you will ... • describe how sound is made. • describe how sounds can be different. • list sources of light we use during the day and at night. • list some ways we use sound and light.
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Go Online! Access interactive content relating to this topic on the NGScience website. ngscience.com
What things around us make sound?
How do people use sound? 133
What Is Sound? Go Online! Try and guess the secret sounds on the NGScience website. QuickCode: G4S2
Close your eyes and listen to the things around you. What can you hear? The things you can hear are sounds. Sound is a form of energy. What sounds can you hear around you? What is making the sounds?
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What Makes Sounds? Stretch an elastic band over a cup. Pluck the elastic band. What do you see? What do you hear? When you pluck the elastic band, it moves back and forth very quickly – it vibrates. When something vibrates, it makes sound. AB
Activities 11.1 – 11.3
How does a guitar make sound?
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Describing Sounds Engineer It! Use materials to design a device that makes different sounds.
Sounds can be loud or soft. A jackhammer makes a loud sound. When you whisper, you make a soft or quiet sound. List some sounds you hear from day to day. Group them as loud or soft sounds.
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Sounds can be high or low. The chirp of a baby chick is a high sound. A moo of a cow is a low sound. AB
Try This! With your friends, talk about the different sounds animals make. Which animals make high sounds? Which animals make low sounds?
Activity 11.4
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Using Sound We use sound in many different ways. We make and use sound when we talk, laugh, cry and sing.
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Things we use, like televisions, radios and computers, make sounds. Sounds made by alarms and sirens are used to alert people.
What are some other ways we use sound? 139
What Is Light? Look out of a window during the day. What do you see? You can see the things outside because of light. Light is a form of energy that helps us to see. During the day, the light from the Sun helps us to see. What are some things that help you to see at night?
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At night there is no Sun to light up the things around us. People use light bulbs, flashlights and candles to help see at night.
Amazing Fact! Sometimes the moon lights up the sky at night. The light from the moon comes from the Sun!
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Sources of Light Something that gives out light of its own is called a source of light. Go Online! Watch a video about sources of light on the NGScience website. QuickCode: S7Z9
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Some sources of light are found in nature. The Sun is a source of light. Fire and lightning are sources of light too.
Flashlights, light bulbs and televisions are sources of light made by people. AB
Activities 11.5 – 11.7
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Light and Shadows Try This! Use a flashlight and your hand to make shadows of different shapes. See if your friends can make the same shaped shadows.
Sometimes an object can block light and make a shadow. A shadow is a dark area.
Look at the shape of the hand and the shape of the shadow. What do you notice? AB
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Activity 11.8
The shape of a shadow is similar to the shape of the object making the shadow. What things are causing the shadows in the photographs?
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Using Light During the day, we use the light from the Sun to help us see the things around us. At night, we use lights to light up our cities, streets and homes. Go Online! Watch a video on the ways we use light on the NGScience website. QuickCode: M2U9
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Cars have headlights that help drivers see at night. Lights also help us to see underwater and underground. You use light when you watch television, play video games, use a computer or use a mobile phone. What are some other ways we use light?
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A Closer Look
Fireflies Some animals can make light of their own. Fireflies are beetles that produce light in their abdomens. They use light to signal other fireflies. Their light also tells other animals ‘Don’t eat me. I taste bad!’.
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Because fireflies produce light of their own – they are a source of light.
See if you can find other animals that produce light of their own. 149
Science Words
sound vibrate loud soft high
low light source of light shadow
Review
1. True or false. (a) We can hear sounds. (b) Sound is made when something vibrates. 2. Write ‘loud’ or ‘soft’ to describe the sounds. (a)
(b)
(c)
(d)
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3. Write ‘high’ or ‘low’ to describe the sounds. (a)
(b)
4. True or false. (a) Light is not a form of energy. (b) Light helps us to see the things around us. 5. List two sources of light. 6. What forms when light is blocked by an object? 7. What is causing the shadows? (a)
(b)
8. List three ways you use light.
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In the Field
An orchestra is a group of people that play musical instruments together to make music. It is important that they play at the right time and they don’t play too loud or too soft. A conductor is a person who stands at the front of an orchestra and lets the musicians know when to play their instrument. They wave their hands to tell the musicians how fast, loud and soft they should play.
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