Understanding
Human Impact
Second graders explore watershed dynamics.
By Robin Magruder and Julia Rosenauer
T
lems (Disinger and Monroe 1994). The North AmericanAssociation of Environmental Education’s (NAAEE)
Ex-cellence in Environmental Education: Guidelines for Learn-ing (K–12) is organized into four strands, all of which
are integrated into this unit. The first strand is related to questioning, analysis, and interpretation skills; students are expected to ask questions and seek answers about the watershed in this unit. The second strand states that en-vironmental education should consider all aspects of the environment, including human interaction; in this unit, students investigate human interactions in the watershed. Strands three and four emphasize skills for understand-ing and addressunderstand-ing environmental issues and personal and civic responsibility, including local and regional points of view related to the environment (NAAEE 2010). Stu-dents should also be able to apply what they have learned to improve the environment through acts having positive impact, creating an increasingly healthy and sustainable society (NAAEE 2010). Throughout this unit, students investigate how their decisions and actions lead to positive and negative consequences in the environment.
We designed our unit with these guidelines in mind, focusing on human impact, both positive and negative, on the living and nonliving components of the local wa-tershed. Investigating the local watershed gave the unit a personal and pragmatic connection to students’ lives be-cause they depend on the local watershed for what they need to live and grow. By investigating creatures living in the watershed and how they are affected by positive and negative habitat impacts, students realized that they can make a difference by making simple choices. Addition-ally, students realized that their decisions affect their lives because they are members of the local watershed as well.
Overview of Unit
In a weekly science enrichment class in an urban Mid-west school, two second-grade classes—composed of 50 students, including seven English Language Learners (ELLs)—participated in the unit, which consisted of five 50-minute lessons with formative assessments. At the end of the unit, we wanted students to have a basic under-standing of the watershed definition provided by Project WET (2002), “A watershed includes all of the land, air, plants, and animals within its borders” (p. xvii). The fo-cus of the first lesson was the geographic components of a watershed from a regional perspective. The second les-son emphasized the living components of the watershed. In the remaining three lessons, students learned about the human impact on watersheds and the ways they could
re-Lesson One: Map the Watershed
“What is a watershed?” students were asked at the be-ginning of the lesson, a question that was met with blank stares. This was not surprising, considering that when asked to identify the parts of a watershed on a preas-sessment, many students selected photos of a shed and a glass of water. The first lesson of our unit was designed to break down vocabulary barriers by providing students with visual and interactive models of a watershed and its components. Students watched an interactive Smartboard video on watersheds (see Internet Resources), in which they were introduced to the visible and invisible parts of a watershed, including land, surface water, groundwater, and atmosphere.After this general introduction, students located their local watershed on the Smartboard using Environmen-tal Protection Agency (EPA) and United States Geo-logical Service (USGS) websites and Google Earth. We explained that all land sits on a watershed, so no matter where we live, we can use technology to help locate the local watershed. Next, students were placed in groups of four to participate in a role-playing activity as drops of water moving to different parts of the watershed based on the roll of a die. We placed each ELL student in a group with at least one academically strong student to provide support and used words and images on posters. To create this activity, we modified the lesson found at Project WET (see Internet Resources) by only including aspects of the watershed relevant to our local watershed. One turn placed a student at the stream station that sub-sequently flowed into the river and then the student was “evaporated.” After 10 turns, students discussed with a partner some of the different places they visited and how they got there. To conclude the lesson, we reviewed the key discussion questions listed below.
• What is a watershed?
• What are some different parts of a watershed? What parts are visible?
• What parts are invisible?
• How does water move to different places in the watershed? What happens when pollution is introduced into a watershed?
Students then completed a formative assessment, Draw
a picture of the watershed and label it with vocabulary from the lesson. Figure 1 includes a student work sample
show-Understanding Human Impact
ing an understanding of key elements of the watershed, including water, precipitation, and landforms. The most common items included in the drawings were landforms, soil, trees, plants, and precipitation.
Lesson Two: Watershed Animals
A week later, the second lesson of our unit began with re-viewing key questions from the first lesson. Next, students brainstormed and listed animals that they thought lived in the local watershed in a think-pair-share format. Students watched a video about local animals living in their water-shed (see Internet Resources), and we added more animals to the brainstorm list.We made the discussion of watershed animals come alive by bringing guppies, a red-eared slider turtle, a pre-served frog, and deer skull with antlers into the classroom. “Will it bite me?” a student asked, wide-eyed, as a red-eared slider was brought closer to him. “Anything with a mouth can bite,” he was reminded by the teacher. “That’s why we only touch animals on their backs away from their faces.” The living turtle was the grand finale; students could barely contain their excitement as each of them took turns touching its shell. Remind students to safely handle animals by keeping their hands away from their mouths and washing their hands thoroughly after touching all animals. Additionally, remind students that they must keep the turtle’s safety in mind by holding it with both hands so that it is not dropped, and that they must treat it with respect. To conclude the lesson, we dis-cussed the things that all animals need to live and how many of these animals meet their needs while living in our local watershed:
• What animals live in the local watershed? What do animals need to live and grow?
• How do the animals displayed in class meet these needs in the local watershed?
The formative assessment asked students to draw an animal from their local watershed and a way that it meets its needs. Figure 2 includes a student work sample show-ing a fish findshow-ing food in the water. Student responses varied and included mammals, birds, fish, and even cave dwellers such as cave shrimp.
Lesson Three: Human Impact
The third lesson of this unit began with a review of the main questions of the first two lessons. Students discussed how humans interact with the watershed by relating to how animals interact with the watershed. Students next watched several video clips related to water pollution and what people, specifically students, can do to decrease wa-ter pollution (see Inwa-ternet Resources). Next, teams of four students played the Watershed Board Game (see Internet Resources). Each student began the game with a cup half-full of water, representing their watershed. Beads, repre-senting pollution, were added or taken out of a student’s cup based on human impact cards drawn during each stu-dent’s turn. Negative examples of human impact included throwing trash in a stream, pouring oil down a sewer drain, and allowing cows to wade in a stream. Positive examples included picking up trash, recycling oil, and keeping cows behind a fence. Human impact cards included simpli-fied language and pictures to assist struggling readers andF I G U R E 1.
Student drawing of watershed
elements.
F I G U R E 2 .
ELL students. For students, the goal of the game was to have the fewest beads in their cup.
After the game, students reviewed some of the harmful and helpful ways in which their watershed was impacted by human activities during the game. This lesson was de-signed with the NGSS crosscutting concept Cause and Effect and NAAEE strand three in mind; these concepts are reflected in the discussion questions:
• How do humans use water?
• Where do you think pollution comes from? • How does pollution affect the animals in a
watershed? How do humans harm the watershed? • How do humans help the watershed?
• Why is it important to have a healthy watershed? • What can you do to help the watershed stay clean
and healthy?
side, illustrate and write a caption of humans helping the watershed. Figure 3 includes a student sample showing
dumping trash into water as harming the watershed and picking up trash helping the watershed. This was the most common response; other responses about harming the watershed included using excessive amounts of water, al-lowing livestock in the watershed, and alal-lowing oil to run off roads into the watershed. Responses about helping the watershed included using rain barrels to reduce consump-tion, fencing off livestock from the watershed, and recy-cling oil to keep it from entering the watershed.
Lesson Four: Sedimentation
The fourth and fifth lessons in the unit linked the first three lessons together and helped students see how hu-mans impact components of the watershed. This lesson began by bringing all students to two stream tables lo-cated in the back of the classroom and observing water be-ing poured over them, causbe-ing sand and silt to be eroded into buckets at the ends of the tables. Because water was involved, students were reminded to walk care-fully to the back of the room so that they would not slip and fall. They also wore eye protection. Students dis-cussed what they witnessed and recalled previous lessons in the school year related to erosion. After students were introduced to effects of sedimentation on a watershed, they brainstormed ways that humans could cause this to occur. This was a difficult concept because most students expressed a simplified image of humans throwing sedi-ment into the stream similar to the simulated activity. To improve understanding, students watched video excerpts discussing human activities related to farming, forestry, and urban development and ways in which these activities contributed to erosion and sedimentation. Students were reminded that animals depend on the watershed, and some animals live in the water. We discussed how an increase of erosion would affect these animals and how increased sedimentation also affected other living things within the food web. Plants, which need light for photosynthesis, were also determined to be negatively impacted by murky water. This lesson was different from other stream table lessons because we focused on the consequences of erosion on animals and humans.
Last, students returned to the stream tables and once again discussed how the land condition could be caused by different human activities depicted in the videos. Af-ter brainstorming, students worked in groups of four to develop a plan for reducing erosion and improving condi-tions in the stream bed. Students shared their plans, and
A student drawing shows how
Understanding Human Impact
as a class, we decided to plant grass seeds in one of our two stream tables for further observation. We left the other stream table alone to act as our control. Consider safety as students work with stream tables; specifically, remind students to not run so they will not slip and fall. Also, ask students to keep the water inside the stream table and not allow it to pour onto the floor. As a formative assessment, students were asked to illustrate one human cause for erosion and sedimentation and how it affects the streambed, including a caption. This was the most difficult assessment for students in this unit. Only seven students were successful, drawing pictures of plant-ing trees or plants in order to prevent erosion. Seven other drawings demonstrated a misconception that when trees are chopped down, they become pollution, showing riv-ers with logs floating in them (Figure 4). These students missed the point that when vegetation is removed from a watershed, more erosion and sedimentation result. The remaining drawings were unrelated to the topic at hand. Because of misconceptions, we revisited the concept of the impact of erosion on the watershed again in the final les-son. We also asked students:
• What is sand and silt?
• How does extra sand and silt get into a streambed? What happens when rainwater hits the land? • How do human activities increase erosion?
• How does extra sand and silt affect streambeds and the animals that live in them?
Lesson Five: Positive Impact
The final lesson began a week later by reviewing key ideas from the previous lessons in the unit and focused on the fourth lesson in which students planted grass in one of the
NAAEE Guidelines
1.F Working with models and simulations —Learners understand that relationships, patterns, and processes can be represented by models.
• Students participate in simulations of watershed components, and human impacts.
• Students model stream tables with and without erosion.
3.1 A Identifying and investigating issues—Learners are able to identify and investigate issues in their local environment and communities.
• Students identify components of their local watershed and use technology to locate key aspects of their own local watershed. 3.1 B Sorting out the consequences of issues. As learners come to understand that environmental and social phenomena are linked, they are able to explore the consequences of issues.
• Students participate in simulations of positive and negative human impacts within a local watershed and connect causes and effects of actions.
stream tables. Because we used fescue, a quick-growing grass, in the week in between, it sprouted and grew on the experimental table. Students were asked to predict which table would produce more erosion and explain their pre-diction to a partner. Next, students observed the effect of “rain” on the table where they planted grass in the previ-ous lesson compared to an identical stream table without grass. Students measured the amount of sedimentation from buckets at the end of both stream tables, and discov-ered that grass decreased the amount of erosion by holding
F I G U R E 4 .
Student drawings reveal
misconceptions.
www.nextgenscience.org/5ess2-earth-systems
The chart below makes one set of connections between the instruction outlined in this article and the NGSS. Other valid connections are likely; however, space restrictions prevent us from listing all possibilities. The materials, lessons, and activities outlined in the article are just one step toward reaching the performance expectations listed below.
Performance Expectations Connections to Classroom Activity
Students:
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.
• observe the effects of rain on rain tables.
• attempt to control erosion by planting grass in a stream table and compare results to a stream table without grass.
Science and Engineering Practices Developing and Using Models
Planning and Carrying Out Investigations
• develop an investigation and construct models of a stream with and without plants to compare the results.
Disciplinary Core Ideas
2-ESS2-1 Compare multiple solutions designed to slow or prevent wind or water from changing the shape of the land.
2ESS2-2 Develop a model to represent the shapes and kinds of land and bodies of water in an area. 2ESS2-3 Obtain information to identify where water is found on Earth and that it can be solid or liquid. 2-LS4-1 Make observations of plants and animals to compare the diversity of life in different habitats.
• compare two water tables.
• create models of many components of the watershed. • use technology to locate their local watershed. • identify animals that live in their local watershed by
touching and interacting with living and once-living animals in the classroom.
• discuss how different plants and animals live in and use different parts of the watershed as their habitat.
Crosscutting Concepts Cause and Effect
Systems and Systems Models
• participate in a game related to positive and negative effects on the watershed caused by human impact. Students consider a negative human impact on the watershed and propose a positive effect to improve the situation.
• participate in a simulation of all components of the watershed and habitat.
Connections to the Common Core State Standards (NGAC and CCSSO 2010)
ELA.SL.2 Participate in collaborative conversations with diverse partners about grade 2 topics with peers and adults in small and larger groups.
• carry on collaborative conversations in all lessons. These conversations include large group, groups of four, groups of two, and with the teacher.
CCSM 2.MD.1 Measure the length of an object by selecting and using appropriate tools such as rulers. • measure the height of sediment in each bucket at the end of the stream tables to compare the amount of
Understanding Human Impact
more of the sand and silt in place. Again, students need eye protection. Remind students to be care-ful around the stream table and to keep the water in the table and off the floor to reduce the risk of slipping and falling.
To further demonstrate the differences between the two stream tables, the teacher collected a vial of water from each bucket and displayed it under a digital microscope for students to compare and describe. To conclude the lesson and unit, we reviewed the human impact cards from lesson three and discussed other ways that humans solve some of the problems that negatively affect the watershed.
As a formative assessment, students worked in pairs to create posters illustrating and describing a negative human impact of their choice and how it can be solved through human actions. These posters reflected what stu-dents learned within the unit. Some ideas in the posters included cleaning up pollution in the watershed, keeping livestock in fences away from the watershed, and reducing the use of sprinklers.
We also asked students:
• What are some ways that humans can help
watersheds? Why is it important to help watersheds? • What could happen if we do not help watersheds?
What can you do to help watersheds?
Conclusion
Overall, we were satisfied with progress students made in their understanding of the watershed and human im-pact. If time allowed, we would have liked to take stu-dents on a field trip to observe several components of the local watershed. ■
Robin Magruder ([email protected]) is an assistant professor of education at Campbellsville University in Campbellsville, Kentucky. Julia Rosenau-er is a science enrichment teachRosenau-er at McFRosenau-erran Prepato-ry Academy in Jefferson County Public Schools, Louis-ville, Kentucky.
NSTA Connection
Download rubrics for each lesson at www.nsta.org/
SC1603.
References
Disinger, J.F., and M.C. Monroe. 1994. Defining environmental education. Workshop Resource Manual. Ann Arbor: University of Michigan.
Kapitan, E., S. Lyttle, and R. Williams. 2013. Discovering the watershed lesson plan. The Nature of Teaching. www. extension.purdue.edu/extmedia/FNR/FNR-476-W%20 Discovering%20the%20Watershed%2013.pdf.
National Governors Association Center for Best Practices and Council of Chief State School Officers (NGAC and CCSSO). 2010. Common core state standards. Washington, DC: NGAC and CCSSO.
NGSS Lead States. 2013. Next Generation Science Standards: For States, by states. Washington, DC: National Academies Press. www.nextgenscience.org/next-generation-science-standards.
North American Association of Environmental Education (NAAEE). 2010. Excellence in environmental education: Guidelines for learning (K–12). Washington, DC: NAAEE Publications and Membership Office.
Project WET. 2002. Discover a watershed: The watershed manager. Bozeman, MT: The Watercourse.
Internet Resources
Cacapon Institute: What Is a Watershed?
www.cacaponinstitute.org/Watershed/What_Watershed. html Discovery Education www.discoveryeducation.com Project WET www.projectwet.org
