Grade 2. In Ecosystem Diversity, students compare diverse habitats and consider the basic needs of various species of living things. The unit begins with an informal pre-assessment in which students brainstorm living and non-living things. Then, the class assembles a set of 6 habitat puzzle posters representing different climates. Throughout the unit, students populate the posters with different types of organisms, reinforcing the idea that all living things have the same basic needs, even though their characteristics can be very unique.
As students populate the habitat posters with decals representing living things, they develop a deeper understanding of plants, mammals, birds, reptiles and amphibians, insects, and fish. Students plant seeds, observe tadpoles, and experiment with models that represent different animal structures, including bones, fur and hair, feathers, exoskeletons, and blubber. Students even put on a play that explores how animals assist in seed dispersal.
At the end of the unit, student groups work collaboratively to create and populate their own habitat puzzle posters. Then, using a poster designed by another group, students independently justify whether the organisms pictured would be able to survive in the habitat based on what they have learned about the plants and animals that inhabit each specific ecosystem.
The Ecosystem Diversity unit addresses the following standards:
Next Generation Science Standards
Disciplinary Core Ideas
- LS2.A: Interdependent Relationships in Ecosystems
- LS4.D: Biodiversity and Humans
- ETS1.B: Developing Possible Solutions
- Systems and System Models
- Cause and Effect
- Structure and Function
- Stability and Change
- Using Mathematics and Computational Thinking
- Asking Questions and Defining Problems
- Developing and Using Models
- Planning and Carrying Out Investigations
- Analyzing and Interpreting Data
- Constructing Explanations and Designing Solutions
- Engaging in Argument from Evidence
- Obtaining, Evaluating, and Communicating Information
Common Core State Standards
American Association for the Advancement of Science Benchmarks
The Nature of Science
- People can often learn about things around them by just observing those things carefully, but sometimes they can learn more by doing something to the things and noting what happens.
- Tools such as thermometers, magnifiers, rulers, or balances often give more information about things than can be obtained by just observing things unaided.
- Describing things as accurately as possible is important in science because it enables people to compare their observations with those of others.
- When people give different descriptions of the same thing, it is usually a good idea to make some fresh observations instead of just arguing about who is right.
The Scientific Enterprise
- Everybody can do science and invent things and ideas.
- In doing science, it is often helpful to work with a team and to share findings with others. All team members should reach their own individual conclusions, however, about what the findings mean.
- A lot can be learned about plants and animals by observing them closely, but care must be taken to know the needs of living things and how to provide for them in the classroom.
The Nature of Mathematics
Patterns and Relationships
- Circles, squares, triangles, and other shapes can be found in nature and in things that people build.
- Patterns can be made by putting different shapes together or taking them apart. Patterns may show up in nature and in the things people make.
The Physical Setting
- The temperature and amount of rain (or snow) tend to be high, low, or medium in the same months every year.
- The sun warms the land, air, and water.
The Living Environment
Diversity of Life
- Some animals and plants are alike in the way they look and in the things they do, and others are very different from one another.
Interdependence of Life
- Animals eat plants or other animals for food and may also use plants (or even other animals) for shelter and nesting.
- Living things are found almost everywhere in the world. There are somewhat different kinds in different places.
Flow of Matter and Energy
- Plants and animals both need to take in water, and animals need to take in food. In addition, plants need light.
Evolution of Life
- Different plants and animals have external features that help them thrive in different kinds of places.
The Mathematical World
- Numbers can be used to count things, place them in order, measure them, or name them.
- Simple graphs can help to tell about observations.
- A quantity is stated as a number and a label, such as 4 inches or 7 blocks.
- Circles, squares, triangles, spheres, cubes, cylinders and other shapes can be observed in things found in nature and in things that people build.
- Some things are more likely to happen than others.
- Some events can be predicted well and some cannot.
- People are more likely to believe your ideas if you can give reasons for them.
- Reasoning can be distorted by strong feelings
- Most things are made of parts.
- Something may not work if some of its parts are missing.
- When parts are put together, they can do things that they couldn’t do by themselves.
- In something that consists of many parts, the parts usually influence one another.
- Something may not work well (or at all) if a part of it is missing, broken, worn out, mismatched, or misconnected.
Constancy and Change
- People can keep track of some things, seeing where they come from and where they go.
- Some things change so slowly or so quickly that the changes are hard to notice while they are taking place.
- Things in nature and things people make have very different sizes, weights, ages, and speeds.
Habits of Mind
Values and Attitudes
- Raise questions about the world and be willing to seek answers to these questions by making careful observations and trying things out.
Manipulation and Observation
- Assemble, take apart, and reassemble constructions using interlocking blocks or other interconnecting pieces.
- Measure the length in whole units of objects using rulers and tape measures.
- Draw pictures that portray some features of the thing being described.
- Interpret pictures, drawings, and videos of real-world objects and events.
- Interpret oral descriptions of real-world objects and events.
- Ask “How do you know?” in appropriate situations and attempt reasonable answers when others ask the same question.
This unit offers several ways to assess students, including a pre- and a post-unit assessment opportunity. Teachers can also use class discussions and charts to assess each lesson. Student activity sheets and science notebook entries—including drawings, writings, and dictated statements—can be used to gauge individual understanding of objectives and key vocabulary throughout the unit. The Assessment Observation Sheets supplied with each lesson help teachers document and measure students’ progress and knowledge using informal assessment. Finally, a general rubric is provided to help teachers evaluate individual students at any point in the unit. The rubric provides a progression of skills and understanding that covers exploration, vocabulary, concept building, and notebook entries.
Lesson 1: Who Lives Around You?
This lesson begins with an informal pre-assessment in which students brainstorm and list living and non-living things. As a class, they construct habitat wall posters by assembling 6 puzzles with backgrounds from different climates. Throughout the unit, students will revisit the habitat posters to reinforce the idea that all living things have the same basic needs, even though some of their characteristics can be very unique.
During an interactive reading activity, students learn more about the characteristics of different climates, and what living things need in order to survive in them. The lesson concludes with students recognizing the difference between living and non-living things, and that the physical characteristics of living things are related to the climates in which they live.
Lesson 2: Living Plants
As students begin to populate the classroom habitat posters with living things, they build an understanding that plants are living things and have specific needs that help them grow. By planting seeds, students are able to manipulate the unique physical environment that is required for plant growth.
Students learn how animals help in seed dispersal by acting out a play with student-made settings and simple costumes. Through actions and conversations among the different characters, they learn the significance of seed dispersal.
Lesson 3: Mammals
In this lesson, students discover that mammals need insulation to cover their bodies to maintain their body temperature. Students learn to measure temperature by reading thermometers to compare warm, lukewarm, and cold water.
Students use their measurement skills to test and observe what happens to the temperature of a thermometer when it is covered with fur or fat. In doing so, students learn that in order to maintain a constant temperature, warm-blooded mammals need insulation.
Lesson 4: Birds
In this lesson, students discover that although the structures of birds are different from those of mammals, their needs are similar. They determine that feathers serve a similar purpose to fur, acting as a form of insulation to maintain the constant body temperature of birds.
Students also learn that one characteristic of most birds is hollow bones. While hollow bones contribute to the light weight of most birds, (which is helpful for flying), students discover that hollow bones make it difficult to swim. Using a hollow straw and a straw filled with salt, students come to the conclusion that some birds such as penguins, which need to swim to catch food in their habitats, do not have hollow bones.
Lesson 5: Reptiles and Amphibians
In this lesson, students differentiate between cold-blooded animals and warm-blooded animals by observing changes in color-changing liquid crystal adhesive dots. They compare and contrast the characteristics of cold-blooded amphibians and reptiles and discover that while they have some characteristics in common, they lay their eggs in different types of places. Students investigate different reasons for the similarities in the bodies of reptiles and amphibians, and for differences in their life cycles.
Lesson 6: Insects
Students continue to compare and contrast organisms as they examine the similarities and differences between the life cycle of an insect and the life cycle of a frog. They also compare and contrast characteristics among insects. Students examine the body of a freeze-dried bee, and simulate a bee’s behavior of flying from one plant to another, thereby showing how bees pollinate plants with their bodies.
Then, by constructing a model of the body of an insect and comparing it to a sample of a real bee (no longer living), they recognize that all insects have the same body parts. Students build an understanding of an insect’s exoskeleton by simulating the molting process insects go through as their bodies grow.
Lesson 7: Fish
In this lesson, students learn that fish have special parts that enable them to live and swim in water. Students then compare and contrast the characteristics of mammals that live in water with those of fish, and recognize that mammals are different from fish because they are warm-blooded whereas fish are cold-blooded. Mammals that live in water must also come up for air and cannot breathe underwater through gills as fish do.
Lesson 8: Diverse Creatures, Diverse Places
In this final lesson, student groups work collaboratively to create and populate their own habitat puzzle posters. Then, using a poster designed by another group, students independently justify whether the organisms pictured would be able to survive in the habitat based on what they have learned about the plants and animals that inhabit each specific ecosystem.