K-ESS2-2 Earth’s Systems

Performance Expectation

K-ESS2-2. Construct an argument supported by evidence for how plants and animals (including humans) can change the environment to meet their needs.

Note to Teachers: While this performance expectation focuses on organisms changing their environment, it is deeply connected to the ESS2.B disciplinary core idea about Earth’s land and water features, and is typically taught alongside map-making activities that help students visualize where land and water are found on Earth. The DCI statement is: “Maps show where things are located. One can map the shapes and kinds of land and water in any area.” Many NGSS-aligned programs address this geographic dimension alongside the living things dimension of this standard.

Assessment Boundary: Assessment does not include climate change impacts or human-caused environmental destruction on a large scale. Focus is on local, observable changes that organisms make.

General Overview

Earth’s surface is covered by a remarkable variety of landforms – mountains, plains, valleys, hills, canyons, deltas – and water bodies – oceans, rivers, lakes, ponds, streams, wetlands, glaciers. Understanding that these features can be represented symbolically on maps is a foundational skill in both science and geography that kindergartners are ready to begin developing.

The map-making dimension of this standard introduces students to one of science’s most important tools: the model. A map is a model – a simplified representation of reality that captures the most important features for a particular purpose while omitting unnecessary detail. When a kindergartner draws a map of their schoolyard showing where the grass is and where the blacktop is, they are doing exactly what professional geographers and earth scientists do.

At the same time, this standard connects to the living world: plants and animals (including humans) don’t just live on Earth’s surface – they change it. Beavers build dams that create ponds. Prairie dogs dig burrow systems that aerate soil. Humans build cities, farms, and roads. Students who understand Earth’s basic land/water geography are better positioned to notice and make sense of these changes.

The crosscutting concept emphasized here is Systems and System Models – the idea that scientists use representations (models) to understand complex systems too large or complex to study directly. Earth’s surface is a system; a map is a model of that system; an argument about how organisms change that system requires understanding what the system looks like in the first place.

Scope and Sequence

What Comes Before

Students enter kindergarten with informal geographic knowledge: they know their home has land around it, they may have seen water bodies (pools, creeks, lakes), and they likely have some exposure to maps through children’s books and media. However, most have not constructed maps themselves or connected map symbols to real features in any systematic way.

At This Grade Level

Students learn that:

1. Earth’s surface has land and water;
2. There are different kinds of land (flat, hilly, mountainous) and different kinds of water (rivers, lakes, oceans);
3. Maps are tools that show where these features are located;
4. We can make our own maps to represent places we know;
5. Organisms, including humans, can change the land and water of their environment.

What Comes After

• In Grade 2, students examine how wind and water change the shape of land (erosion and deposition – 2-ESS2-1) and use maps and models to identify land and water bodies (2-ESS2-2, 2-ESS2-3).
• By Grade 4, students study how Earth’s features have changed over geological time through erosion, volcanoes, and earthquakes.
• By Grade 5, students investigate the role of Earth’s systems (geosphere, hydrosphere, atmosphere, biosphere) in shaping the surface. The map-literacy and spatial reasoning developed in kindergarten is the entry point for all of this later work.

What Students Must Understand

About Earth’s Surface

• Earth’s surface has both land and water, and these are distributed in patterns that can be observed and mapped.
• There are different kinds of land (flat/plains, hilly, mountainous, sandy) and different kinds of water (rivers that flow, lakes and ponds that are still, oceans that are vast and salty).
• Most of Earth’s surface is covered by water (though students don’t need precise percentages at this level – just a general understanding that water is abundant and widespread).
• Land and water features have different names that scientists and geographers use: mountain, valley, plain, river, lake, ocean, pond, stream, bay, peninsula, island.

About Maps as Models

• A map is a picture that shows where things are located from a “bird’s eye view” (looking down from above).
• Maps use symbols and colors to represent real things (blue for water, green or brown for land are common conventions).
• A map can represent any area, from a classroom to the whole Earth.
• A map is a model – it is not the real thing, but it helps us understand the real thing by showing patterns and relationships.

About Organisms Changing the Environment

• Organisms (plants, animals, humans) do not just live in their environment passively – they actively change it to meet their needs.
• Examples of animals changing the environment: beavers build dams; birds build nests; earthworms move soil; elephants knock down trees.
• Examples of humans changing the environment: building houses, roads, farms; planting gardens; digging wells; making parks.
• Some changes to the environment are helpful for some organisms but may be harmful for others – this idea will be developed more deeply in later grades.

Key Vocabulary

Land, water, map, model, symbol, ocean, river, lake, pond, stream, mountain, hill, valley, plain, island, peninsula, coast, environment, change, dam, habitat.

Lesson Ideas and Activities

Activity 1: Mapping Our Schoolyard

Overview: Students go outside and observe the schoolyard, then come inside and create a simple map of it from a bird’s-eye view. They identify areas of grass, blacktop, garden beds, trees, and any water features (drinking fountains, puddles after rain).

Materials: Large paper or pre-drawn outline of the school building; crayons in multiple colors; clipboards for outdoor observation.

Procedure: (1) Take students outside. Ask: “If a bird was flying above our school, what would it see?” (2) Walk around the schoolyard together, identifying features. (3) Return inside and create maps using colors to distinguish land-type areas from each other. (4) Share and compare maps – notice similarities and differences.

Discussion: “What did you show on your map with blue? Brown? Green? Why those colors?” Introduce the word “symbol” and the idea that maps use symbols to stand for real things.

Activity 2: Globe Exploration – Land and Water

Overview: Students examine a classroom globe, placing their hand on it and noticing how much of their hand touches blue (water) versus other colors (land). This kinesthetic activity builds the intuition that Earth has a lot of water.

Materials: One or more classroom globes; inflatable globes (one per pair of students is ideal).

Activity: Students spin an inflatable globe and catch it with one hand, recording whether their right index finger is touching land or water. Repeat 10 times. Tally and discuss results. Students will observe that their finger lands on water most of the time – a striking, memorable experience of Earth’s water-covered nature.

Discussion: “What did you notice? Why do you think so much of our globe is blue? Where does all that water come from? How is the water on the globe different from the water in a glass?”

Activity 3: Animals That Change Their Home

Overview: Read aloud a picture book featuring animals that change their environment (e.g., a book about beavers building dams). Then students draw a “before and after” showing how the environment changed and why.

Suggested Books: “Beavers” by Gail Gibbons; “The Busy Little Squirrel” by Nancy Tafuri; “Animals at Work” (various).

Sentence Starters: “The ___ changed the environment by ___. It did this because ___. After the change, the environment looked like ___.”

Extension: Make a class list of all the ways humans change the environment in and around school. Sort: which changes seem helpful? Which seem harmful? Why?

Activity 4: Make a Landform/Water Body Sculpture

Overview: Using playdough, sand, or clay in a tray, students create a model of an imaginary landscape that includes at least two types of land and two types of water. They then draw a map of their model from above.

Materials: Aluminum foil trays or shallow bins; blue-tinted water; brown/green playdough or clay; blue food coloring for water areas.

Learning Goal: Students experience firsthand the relationship between a 3D landscape and a 2D map, and practice using color-coding conventions.

Activity 5: Field Research – How Have Humans Changed This Place?

Overview: Take students on a walk near school (or look at historical photos if available). Ask them to look for evidence that humans have changed the land – buildings, roads, parks, gardens, fences, paved areas.

Recording: Students use clipboards to draw what they see. Back in class, share: “What did humans build here? What was here before? How do you know?” If historical aerial photos of the neighborhood are available, compare them to the current view.

Common Student Misconceptions

Misconception 1: “Maps look like photographs.”

What students think: Many children expect a map to look like a realistic photograph of a place. They may be confused by the abstract, bird’s-eye-view, symbolic nature of maps.

How to address it: Show satellite imagery alongside a traditional map of the same area. Point out: “This is a photograph taken from space. This is a map of the same area. How are they different? Why might the map be useful even though it doesn’t look as realistic?”

Misconception 2: “Rivers flow uphill sometimes.”

What students think: Children who haven’t explicitly thought about it often don’t realize that rivers always flow downhill due to gravity. They may think rivers can flow in any direction depending on where people want them to go.

How to address it: Demonstrate water flow using a tilted tray with water. Ask: “Which way does the water flow? Why? What would happen if we tilted the tray the other way?” Rivers always flow from higher to lower elevation – this is a key concept for later earth science learning.

Misconception 3: “The ocean water is the same as the water we drink.”

What students think: Children often don’t distinguish between fresh water and salt water. They may not know that most of Earth’s water is ocean water, which is too salty to drink.

How to address it: Bring in a small container of salt water and fresh water. Let students (carefully) taste each (or smell each if health protocols prevent tasting). Ask: “Which would you drink if you were thirsty? Why? Why do you think the ocean is salty?”

Misconception 4: “Changing the environment is always bad.”

What students think: As students begin to learn that humans change the environment, many initially assume all change is harmful because of prior exposure to environmental messaging about pollution and habitat loss.

How to address it: Present examples of beneficial environmental changes: restoring wetlands to provide habitat, planting trees to reduce erosion, building bird houses to provide nesting sites for cavity-nesting birds. Discuss: “Is every change to the environment harmful? Can some changes be helpful? For whom?”

Misconception 5: “Mountains are always near the ocean.”

What students think: From picture books and media, children may have formed the belief that dramatic landscapes (mountains, ocean cliffs) are the norm. They may not appreciate that vast flat plains, gentle rolling hills, and inland water bodies are equally common.

How to address it: Look at maps and images of diverse landscapes – the Great Plains, the Midwest, the Colorado Plateau, coastal marshes. Help students see that Earth’s surface is remarkably diverse and that no single type of landscape dominates.

Assessment Questions

Map and Spatial Reasoning

1. (Show a simple map) Point to the land on this map. Point to the water. How do you know which is which?
2. What color do maps usually use for water? Why do you think maps have symbols and colors instead of looking like photographs?
3. Draw a map of our classroom. What would you include to help someone find their way around?

Land and Water Features

4. What is the difference between a river and a lake? How are they the same?
5. If you were a fish, where could you live on Earth? What kinds of water bodies might be your home?
6. (Show a globe) What do you notice about how much land and water there is on Earth?

Organisms and Environmental Change

7. Can animals change the environment? Can you think of an example?
8. A beaver cuts down trees and builds a dam in a stream, making a pond. How did the beaver change the environment? Who might benefit from this change? Who might it cause problems for?
9. Think about the building our school is in. Did humans change the environment to build it? What might have been here before the building?

Evidence and Argument

10. A student says: “Animals never change their environment – they just live in it.” Do you agree? What evidence would you use to disagree?
11. Look at these two pictures of the same place – one from 50 years ago and one from today. What changed? What caused those changes?

Cross-Curricular Connections

Social Studies / Geography

Map-making is a core skill in elementary social studies. This activity directly supports NCSS geography standards and builds foundational spatial literacy for all future map use. Students also connect geographic features to human settlement patterns: Why do many cities develop near rivers? Why do people build homes near flat land rather than steep mountains?

Mathematics

Spatial reasoning, geometric thinking (shapes of landforms on maps), measurement (relative sizes of land and water bodies), and fraction concepts (approximately 71% of Earth’s surface is water, though precise percentages are not expected at this level).

Art

Map-making is inherently artistic. Students make design decisions about color, symbol, and representation. Introduce the work of professional cartographers and their beautiful, hand-illustrated historical maps.

Literature

Maps appear in countless picture books and chapter books – from treasure maps to fantasy world maps. Use literature as an entry point: “This book has a map in the front. Let’s look at it. What land features do you see? What water features?”

Teacher Background Knowledge

Earth’s Surface Distribution: Approximately 71% of Earth’s surface is covered by water. Of that water, about 97% is salt water in the oceans. Only about 3% is fresh water, and most of that is locked in glaciers and ice caps. This means only about 0.3% of Earth’s total water is accessible fresh water in rivers, lakes, and groundwater – a striking statistic that becomes increasingly important as students progress through grades.

Major Landform Types: Mountains (formed by tectonic uplift or volcanism), hills (gentler elevations), plains (flat lowlands), valleys (low areas between hills/mountains), plateaus (elevated flat areas), deltas (fan-shaped deposits where rivers meet larger water bodies), canyons (deep, narrow valleys carved by rivers).

Major Water Body Types: Ocean (vast, salty; Earth has five: Pacific, Atlantic, Indian, Southern, Arctic); sea (smaller saltwater body, often partially enclosed by land); lake (enclosed water body, usually fresh water); river (flowing water body that eventually drains to ocean, sea, or lake); stream (smaller flowing water body); pond (small, enclosed, shallow water body); wetland (land area saturated with water – swamps, marshes, bogs).

How Maps Work: Maps are two-dimensional representations of three-dimensional reality. Different types of maps show different information: political maps show country/state boundaries; physical maps show elevation and terrain; thematic maps show any specific topic (rainfall, population, temperature). All maps use symbols, scales, and usually a legend (key). Basic cartographic conventions include: blue = water; green/brown = land; lines of latitude and longitude for location; a scale bar for distance.