GRADE 3 | UNDERSTANDING LIFE SYSTEMS
GROWTH AND CHANGES IN PLANTS
OVERVIEW
Growth and Changes in Plants focuses on the characteristics and requirements of plants and the ways in which plants grow. Students will observe and investigate a wide variety of local plants, from trees and mosses in their natural environment to flowers and vegetables grown at school or on farms, and will consider the impact of human activity on plants and their habitats. Students will also learn about the importance of plants as sources of oxygen, food, and shelter, and the need for humans to protect plants and their habitats.
In preparation for working with plants, it is important that students be able to identify practices that ensure their personal safety and the safety of others and to demonstrate an understanding of the importance of these practices. This includes knowing why they should not taste any part of a plant unless directed to do so by a teacher, and why they should wash their hands after handling plants or parts of plants.
This topic also provides opportunities for connecting to the Grade 3 social studies topic Canada and World Connections: Urban and Rural Communities. As students look at similarities and differences between regions, they can consider the kinds of plants that help to make a location unique. They can also consider the need to protect farmlands as plant habitats and as producers of food for living things. Connections can also be made with the Grade 3 social studies topic Heritage and Citizenship: Early Settlements in Upper Canada, as students look at the types of plants that were used both by Aboriginal people and the settlers, plants that were native to the area, and plants that were introduced by the settlers. Connections can also be made with another Grade 3 science and technology topic, Understanding Earth and Space Systems: Soils in the Environment.
Fundamental Concepts: Systems and Interactions
Big Ideas:
• Plants have distinct characteristics. (Overall expectations 2 and 3)
• There are similarities and differences among various types of plants. (Overall expectation 2)
Fundamental Concepts: Sustainability and Stewardship
Big Ideas:
• Plants are the primary source of food for humans. (Overall expectation 1)
• Humans need to protect plants and their habitats. (Overall expectation 1)
• Plants are important to the planet. (Overall expectation 1)
OVERALL EXPECTATIONS
By the end of Grade 3, students will:
1. assess ways in which plants have an impact on society and the environment, and ways in which human activity has an impact on plants and plant habitats;
2. investigate similarities and differences in the characteristics of various plants, and ways in which the characteristics of plants relate to the environment in which they grow;
3. demonstrate an understanding that plants grow and change and have distinct characteristics.
SPECIFIC EXPECTATIONS
1. Relating Science and Technology to Society and the Environment
By the end of Grade 3, students will:
1.1 assess ways in which plants are important to humans and other living things, taking different points of view into consideration (e.g., the point of view of home builders, gardeners, nursery owners, vegetarians), and suggest ways in which humans can protect plants
Sample prompts: Plants provide oxygen and food that other living things need to survive. Plants use and store carbon dioxide, helping reduce the amount of this greenhouse gas in the atmosphere. Trees reduce humans' energy use in summer by providing cooling shade. Leaves, twigs, and branches of trees and shrubs block erosion-causing rainfall. Grass and shrubs prevent soil from washing away. Roots, leaves, and trunks provide homes for wildlife. Aboriginal people use plants for many medicines.
1.2 assess the impact of different human activities on plants, and list personal actions they can engage in to minimize harmful effects and enhance good effects
Sample prompts: When humans provide common house plants and blooming potted plants with an appropriate environment, they help fight pollution indoors. When humans plant trees, they benefit the environment in many different ways. When humans fill in wetlands to build houses, they destroy an important habitat that supports many plants. When humans pick wildflowers or dig them up to replant in their home gardens, they harm a natural habitat that supports many living things. When humans plant non-native plants and trees that need pesticides and/or a lot of water to survive, they drive out native plants and trees that are adapted to our climate and that provide habitat and food for native birds, butterflies, and mammals.
2. Developing Investigation and Communication Skills
By the end of Grade 3, students will:
2.1 follow established safety procedures during science and technology investigations (e.g., avoid touching eyes when handling plants; never taste any part of a plant unless instructed to do so by the teacher)
2.2 observe and compare the parts of a variety of plants (e.g., roots of grass, carrot, dandelion; stem of cactus, carnation, tree; leaves of geranium, spider plant, pine tree)
2.3 germinate seeds and record similarities and differences as seedlings develop (e.g., plant quick-growing seeds – nasturtium, morning glory, sunflower, tomato, beet, or radish seeds – in peat pellets to observe growth)
2.4 investigate ways in which a variety of plants adapt and/or react to their environment, including changes in their environment, using a variety of methods (e.g., read a variety of non-fiction texts; interview plant experts; view DVDs or CD-ROMs)
2.5 use scientific inquiry/experimentation skills (see page 12), and knowledge acquired from previous investigations, to investigate a variety of ways in which plants meet their basic needs
Sample guiding questions: How do plants meet their need for air, water, light, warmth, and space? What are different ways in which we can help plants meet their needs?
2.6 use appropriate science and technology vocabulary, including stem, leaf, root, pistil, stamen, flower, adaptation, and germination, in oral and written communication
2.7 use a variety of forms (e.g., oral, written, graphic, multimedia) to communicate with different audiences and for a variety of purposes (e.g., make illustrated entries in a personal science journal to describe plant characteristics and adaptations to harsh environments)
3. Understanding Basic Concepts
By the end of Grade 3, students will:
3.1 describe the basic needs of plants, including air, water, light, warmth, and space
3.2 identify the major parts of plants, including root, stem, flower, stamen, pistil, leaf, seed, and fruit, and describe how each contributes to the plant's survival within the plant's environment (e.g., the roots soak up food and water for the plant; the stem carries water and food to the rest of the plant; the leaves make food for the plant with help from the sun; the flowers grow fruit and seeds for new plants)
3.3 describe the changes that different plants undergo in their life cycles (e.g., some plants grow from bulbs to flowers, and when the flowers die off the bulb produces little bulbs that will bloom the next year; some plants grow from germination of a seed to the production of a fruit containing seeds that are then scattered by humans, animals, or the wind so that new plants can grow)
3.4 describe how most plants get energy to live directly from the sun (e.g., plants turn the energy from the sun into food for themselves) and how plants help other living things to get energy from the sun (e.g., Other living things, which cannot "eat"sunshine, eat the plants to get the energy. They also get energy when they eat the animals that eat the plants.)
3.5 describe ways in which humans from various cultures, including Aboriginal people, use plants for food, shelter, medicine, and clothing (e.g., food – from rice plants; houses for shelter – from the wood of trees; medicines – from herbs; clothing – from cotton plants)
3.6 describe ways in which plants and animals depend on each other (e.g., plants provide food for energy; animals help disperse pollen and seeds, and provide manure that fertilizes the soil in which plants grow; plants need the carbon dioxide that animals breathe out, and animals need the oxygen that plants release into the air)
3.7 describe the different ways in which plants are grown for food (e.g., on farms, in orchards, greenhouses, home gardens), and explain the advantages and disadvantages of locally grown and organically produced food, including environmental benefits
3.8 identify examples of environmental conditions that may threaten plant and animal survival (e.g., extreme heat and cold; floods and/or droughts; changes in habitat because of human activities such as construction, use of gas-powered personal watercraft on lakes)