Grade 2. In 6 lessons spanning 33 class sessions, Earth Materials takes students on an exploration of water, rocks, sand, soil, landforms, and bodies of water. Students begin to formulate an understanding that the land is constantly changing, usually over a long period of time (although some changes to the land occur quickly, such as those caused by volcanoes and flash floods). Students also start to realize that wind and water erosion can change the shape of the land.
The understanding that water and wind can change earth materials over time underpins all the explorations of earth materials throughout the unit. The class investigates how vegetation and moist sand on sand dunes can slow or stop wind erosion, and they design solutions to slow or prevent wind erosion by creating a wind barrier.
As a culminating post-assessment activity, students apply what they’ve learned to develop a plan to build a model island, incorporating bodies of water and landforms. Students present their landform models and convey the impact erosion will have on at least one of the landforms represented.
The Earth Materials unit addresses the following standards:
Next Generation Science Standards®
- 2-ESS1-1: Use information from several sources to provide evidence that Earth events can occur quickly or slowly.
- 2-ESS2-1: Compare multiple solutions designed to slow or prevent wind or water from changing the shape of the land.
- 2-ESS2-2: Develop a model to represent the shapes and kinds of land and bodies of water in an area.
- 2-ESS2-3: Obtain information to identify where water is found on Earth and that it can be solid or liquid.
- 2-PS1-1: Plan and conduct an investigation to describe and classify different kinds of materials by their observable properties.
Disciplinary Core Ideas
- ESS1.C: History of the Planet
- ESS2.A: Earth Materials and Systems
- ESS2.B: Plate Tectonics and Large-Scale System Interactions
- ESS2.C: The Roles of Water in Earth’s Surface Processes
- PS1.A: Structure and Properties of Matter
Science and Engineering Practices
- Constructing Explanations and Designing Solutions
- Developing and Using Models
- Obtaining, Evaluating, and Communicating Ideas
- Planning and Carrying Out Investigations
- Stability and Change
- Influence of Engineering, Technology, and Science and the Natural World
- Science Addresses Questions About the Natural and Material World
Common Core State Standards
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. 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. Finally, a summative assessment gives students the opportunity to demonstrate unit-specific content knowledge by responding to questions in a variety of formats.
Lesson 1: Water World
In Lesson 1, students build an understanding of the relevance that water has on Earth. Since water plays a part in shaping land, it is important to know where water can be found and how water cycles on Earth. Students use maps, models, and graphs to discover where and how water impacts Earth. The class is introduced to the Land and Water Card Set, which they will use to explore landforms and bodies of water throughout the unit.
Lesson 2: Rock Attributes: How Are Rocks Different?
This lesson focuses on one natural earth material: rocks. Students explore the different types of rocks—igneous, sedimentary, and metamorphic—found in a Rock Study Kit, and classify rocks by a variety of attributes and properties. In a Family Science Activity, students find rocks at home and bring in one rock for a class rock museum. Students explore the rocks in the museum, and create a Venn diagram to classify the museum samples.
Lesson 3: What Is Sand?
In an opening discussion, students share their prior knowledge of sand. Working in pairs, students explore the properties of sand, rocks, and gravel, and realize that sand is made when rocks break down by erosion over time. Students also compare the attributes of wet and dry sand. Students begin to understand that water and wind can change earth materials over time. Finally, the class explores how vegetation and moist sand on sand dunes can slow or stop wind erosion, and they design solutions to wind erosion by creating a wind barrier. Students engage in discussions and record their findings on activity sheets, on class charts, and/or in their science notebooks throughout the lesson.
Lesson 4: What Is Soil?
The lesson begins with students sharing their prior knowledge of soil and making preliminary observations. Using many of the same strategies they practiced in Lesson 3, students work in pairs to explore the properties of soil. They make more complex comparisons: dry soil is compared with wet soil, and soil is compared with sand. Students use activity sheets to record these observations, and then the class sets up a settling jar to observe over time.
Students take a trip to the schoolyard to collect local soil. Students also observe the local soil they collected and try to identify components such as sand, silt, clay, and loam. In a final activity, students learn about soil erosion and the effects on the land when soil is eroded by wind and water. They also learn about solutions to slow down or stop the effects of soil erosion.
Lesson 5: Changes in the Land
In this lesson, students continue to explore how earth materials such as rocks and minerals, sand, soil, and water are constantly changing the land through erosion. They also continue to build on their understanding that wind and water can change the shape of the land. Students expand their exploration of landforms and bodies of waters by continuing to use the Land and Water Card Set. Students investigate how glaciers shape and change the land over time and how a river forms a canyon.
Lesson 6: Making Model Landforms
Students continue to review landforms and bodies of water using the Land and Water Card Set. As a culminating post-assessment activity, students apply what they’ve learned to develop a plan to build a model island, incorporating bodies of water and landforms. Students present their landform model individually to the class, and convey the impact erosion will have on at least one of the landforms in their model.