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Is Our Water Healthy?

Unit Plan: Water Quality & HealthTime: Two-three 45-minute periods Setting: Classroom, aquatic ecosystem
6-8, 9-12Hudson River Ecology
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Students will decide whether their local stream or the larger Hudson River are healthy, using chemical and physical characteristics, and be able to collect data to support or negate their hypotheses.


    1. Students test water quality parameters at a local stream, pond, or other aquatic system.
    2. Students return to the aquatic ecosystem to take repeat measurements.
    3. Students compare their data with current HR-ECOS data.


    • Metersticks
    • Measuring tape
    • Thermometers (air and water)
    • Orange or ping-pong ball
    • Stopwatch
    • Waders or appropriate shoes
    • Dissecting trays, tweezers, nets to observe benthic material, ID cards (optional)
    • Test kits for DO, phosphates, nitrates, pH, chloride and other appropriate tests
    • Goggles, gloves
    • Data sheets- stream/river, pond/lake, chemistry, hypothesis sheets

    Preparation: Prepare the students using lesson 1 in this module. You should also decide whether you want to include macroinvertebrates in your survey. If so, use the collection techniques in the lesson titled “Aquatic Ecosystem Exploration”.

    Engage: Show students a map of the local watershed and/or the Hudson River watershed. Ask: What do you know about the water quality here? How could you find out? How often do you have to test? Where? What else would you have to know? Together with students, define baseline data. Review safety procedures for outdoor work.

    Explore 1: In groups, students will test the water quality and make observations about the physical characteristics of a stream or pond (optional: macroinvertebrate collection). Data sheets are provided for both types of ecosystems. Based on the size of your class, you will want to assign groups different variables to test. Decide as a class how you want to sample the stream; do you want to split groups up to sample different areas, or will everyone work in one area? Visit the stream and allow the students to gather their respective data for about 20 minutes (or when all groups seem finished with the survey). All students should do a detailed site drawing.

    Explain 1: After you return to the classroom, discuss student findings. What did students notice? If students collected macroinvertebrates, discuss the connections between the organisms that live in/near stream with the physical characteristics of that stream.

    Explore 2: When students have discussed the initial surveys, allow time in their groups to develop hypotheses. Have the group hypothesize how each stream characteristic that they observed might change (or not) over the course of the year, at different locations, or whatever other variable you decided to use. Conduct the second and subsequent testing during the remainder of the school year.

    Explain 2: Students may or may not be able to measure physical changes or chemical changes. If possible, return to the stream a few more times to collect more data. Encourage students to determine the validity of their data based on the limitations of a school setting (ie limited class time, inability to measure during a storm, at the source of pollution, etc). While students are writing up their lab reports, they are asked to think about the difference between a ‘bend’ and a ‘break’ in an ecosystem (a temporary vs a permanent change). If this is a difficult concept for students, spend some time discussing what this might mean for a stream versus a larger ecosystem such as a river. Ask students to classify different environmental problems as ‘bends’ or ‘breaks’.

    Extend: Students can create a presentation on their research for community members or other audiences within the school.

    Evaluate: Students turn in the completed hypotheses and data sheets, along with a lab report.


    Lesson Files

    Hypothesis Worksheet
    Lab Report
    Pond Ecosystem Data Sheet
    Chemical Test Data Sheet
    Stream Ecosystem Data Sheet

    Benchmarks for Science Literacy

    1B Scientific Inquiry, 1C The scientific enterprise, 2A Patterns and Relationships, 4B The Earth, 4C Processes that shape the earth, 5A Diversity of Life, 11C Constancy and Change, 12B Computation and Estimation, 12D Communication Skills

    NYS Standards

    MST 1 - Mathematical analysis, scientific inquiry, and engineering design, MST 4- Physical setting, living environment and nature of science, MST 6- Interconnectedness of mathematics, science, and technology (modeling, systems, scale, change, equilibrium, optimization)
    Next Generation Science Standards

    Science and Engineering Practices

    Asking questions and defining problems, Planning and carrying out investigations

    Cross Cutting Concepts

    Patterns, Cause and effect

    Disciplinary Core Ideas

    LS2A: Interdependent Relationships in Ecosystems
    New York State Science Learning Standards

    Performance Expectations

    MS-LS2-4. Construct an argument supported by empirical evidence that changes to physical or biological components of an ecosystem affect populations., MS-ESS3-3. Apply scientific principles to design a method for monitoring and minimizing a human impact on the environment.*, HS-ESS2-5. Plan and conduct an investigation of the properties of water and its effects on Earth materials and surface processes., HS-ESS2-7. Construct an argument based on evidence about the coevolution of Earth’s systems and life on Earth., HS-ESS3-4. Evaluate or refine a technological solution that reduces impacts of human activities on natural systems.