Grade Three Snapshot 4.4: Living Things in Changing Environments
Anchoring phenomenon: Some places on the schoolyard have lots of plants and animals while other places have fewer.
Ms. J introduces her students to the idea of environmental changes (CA EP&C II) by taking her class on a field trip to visit the campus, surrounding neighborhood, and a local park. In preparation for this activity: Ms. J identified three areas near the school where her students could see plants and animals, and observe the effects of human activities; she also enlisted a parent volunteer to go along. Before going outside, Ms. J explains to the students that they will be going on a local field trip to make observations and collect evidence about environmental changes on campus and in the local neighborhood. She tells them to bring pencils and their science journal so that they can make notes about their observations.
While walking around campus, the students observe and ask questions [SEP-1] about why there are very few plants and animals on the school grounds. Ms. J has them make notes about their observations and record any questions in their science notebooks during their investigation [SEP-3] of environmental changes in the local area. The class walks down the street, making observations and taking notes as they go by the houses and apartment buildings in the neighborhood. They observe that some areas have green spaces with different kinds of plants and animals, and see many birds sitting on the branches of the bushes and squirrels running through the yards. Finally, Ms. J takes them to visit a local park where they see even more plants and animals. As they walk back to the school, Ms. J kicks off a discussion by asking students if they observed any patterns [CCC-1] regarding the variety and numbers of plants and animals they observed in the three different areas.
Back in their classroom, Ms. J guides a student discussion of similarities and differences among the areas they visited during their “field trip.” She makes a four-column list on the board labeled “Place,” “Description of Area,” “Plants We Saw,” and “Animals We Saw.” With their data recorded, Ms. J asks the students to contribute to a list of the differences in plants and animals among the three habitats: campus, neighborhood, and park. The class then begins a discussion to analyze and interpret [SEP-4] the data they collected and begins thinking about the causes [CCC-2] of these differences. Students identify several human activities, such as, removing trees, making streets, paving the campus, and building houses. Once they complete their list, Ms. J asks students to identify the evidence they saw during their field trip that supports the argument [SEP‑7] that changes in habitats affect the organisms living there. Some organisms can survive well, some survive less well, and some cannot survive at all. Ms. J records the students’ evidence on the board.
Investigative phenomenon: Sweetwater Marsh is changing.
Ms. J recognizes the importance of developing her students’ awareness that environmental changes they observe locally also occur throughout California. She uses the leveled reader, Sweetwater Marsh National Wildlife Refuge, as the basis for student investigations of how humans have changed a rapidly disappearing coastal habitat (CA EP&C II), which serves as a breeding ground and nursery for many of the fish that people eat (CA EP&C I).
Using information the students gathered from the reading, the class makes a mural with “before” and “after” sections where some students draw the original habitat and others show the habitat after human activity. The students’ drawings illustrate some changes, for example, the addition of buildings, roads, and levees. This reading and mural served as the context for a discussion of how the functioning and health of ecosystems are influenced by their relationships with human societies.
To reinforce the crosscutting concept about systems and system models [CCC-4], Ms. J reminds the students that ecosystems are an example of a system. She asks them to identify the salt marsh ecosystem components on their mural. Several students point out the birds nesting in the plants as an example of an interaction among the components of the ecosystem.
After completing their mural, Ms. J asks the students several questions about the marsh, its plants and animals, and how the habitat might change if more human-activity occurs there. She focuses the students on environmental changes asking them to predict answers to questions like, “Which plants or animals will be affected if the water becomes saltier?” and “If the water in all of the San Diego Bay becomes muddier, what might happen?” Based on their notes and the class discussion, students identify the main idea of the lesson, human activities have resulted in changes to the natural habitat, which in turn have decreased the number and variety of plants and animals in the area.
Resources
California Education and the Environment Initiative. 2013. Sweetwater Marsh National Wildlife Refuge. Sacramento: Office of Education and the Environment. http://californiaeei.org/framework/sci/Sweetwater