Overview: In this investigation, students develop understanding of the water cycle through two separate activities.

In the previous activity 2A: Water Cycle Simulation, students took part in a simulation of water moving through the water cycle through various paths, visiting eight stations around the classroom. They recorded and reflected on their journey and then built simple water cycle models using ziplock bags or jars.

In Activity 2B: Dirty Water/Clean Water, students learn about water pollution and wastewater treatment through a visit from a local “expert,” and make posters or presentations to share and clarify their understanding.

Focus Questions:

• How does water move through the water cycle?

• Why don’t we run out of water?

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Engagement: (20 minutes)

Ask students to review their notes in their science notebooks from the previous activity and to compare or share what they have learned about the water cycle with a partner or team.

Ask them to where they think the water goes after they use it, and generate a list of questions about this portion of water’s journey.

Next, have the students draw what they think a septic system or water treatment system might look like. Using their science notebooks, they brainstorm and write down the questions they have about how a waste treatment system works.

Exploration: (20-40 minutes)

Students will listen to a guest speaker, take notes in their science notebooks, and ask questions about water treatment or the effects of water pollution.
The speaker might be:

• A local wastewater treatment supervisor
• A village clean water technician
• A representative of the local soil and water conservation district
• A civil engineer with wastewater expertise.

If you cannot get a guest speaker, and do not have a treatment facility to tour, you can show students the following virtual tours of wastewater treatment plants in other locations:

Blue Plains Wastewater Treatment (District of Columbia)

Wastewater Treatment for Youngsters

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Explanation: (1 class period or more)

Ask students to draw a new “map” or write a description of where water goes after we use it, in their science notebooks.

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Elaboration: (1 class period or more)

Ask students to choose a method to share what they have learned about where water comes from and where it goes. They might create a display or poster for the class or school showing all the components of the journey of water through their watershed. Other products could include a Powerpoint presentation, skit, or brochure.

What is a Septic Tank? is a lesson/activity to create a model septic tank. 

Additional information related to wastewater and wastewater treatment:
What Happens After the Flush?

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Evaluation:

Using their student notebooks, students look at their original description and/or drawing of the water cycle. Ask if they are able to add more details to their drawing. Answer the question: Where does the water go after we have used it?

Teacher assesses student notebooks. 

Teacher Preparation:

Arrange for a guest speaker to talk to the students about liquid waste disposal, water treatment, or water pollution. Check with guest to see if a projector or computer is needed for their presentation.

Students will review their notes in their science notebooks from the previous day’s investigation. They will compare or share with a partner or team of students to see what they have learned about the water cycle. They will brainstorm questions to ask the guest speaker. They will take notes when the speaker is explaining water treatment. 

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Curricular Connections:

Math. Students can tally the number of times they visited each location in the water cycle simulation, and make a graph of their class totals. The graph can be recorded in their science notebook.

Social Studies. It may enhance students’ understanding of local systems if they investigated rural vs. urban waste water treatment, and permafrost vs. no permafrost regions of Alaska.  This may be extended into the study of Alaska’s physical and human geography and cultures, which is part of the 3rd grade Alaska Social Studies GLEs.

Alaska Science Grade Level Expectations Addressed:

2nd Grade Standards Addressed:

Science as Inquiry and Process
SA Students develop an understanding of the processes and applications of scientific inquiry.
SA1 Students develop an understanding of the processes of science used to investigate problems, design and
conduct repeatable scientific investigations, and defend scientific arguments.
SA2 Students develop an understanding that the processes of science require integrity, logical reasoning, skepticism,
openness, communication, and peer review.
Concepts of Physical Science
SB2 Students develop an understanding that energy appears in different forms, can be transformed from one form to another, can be transferred or moved from one places or system to another, may be unavailable for use, and is ultimately conserved.
Concepts of Earth Science
SD Students develop an understanding of the concepts, processes, theories, models, evidence, and
systems of earth and space sciences.
SD1 Students develop an understanding of Earth’s geochemical cycles.

3rd Grade GLEs Addressed:

The student demonstrates an understanding of the processes of science by:
[3] SA1.1 asking questions, predicting, observing, describing, measuring, classifying, making generalizations, inferring, and communicating.

[3] SA1.2 observing and describing the student’s own world to answer simple questions.

The student demonstrates an understandingof the attitudes and approaches to scientificinquiry by
[3] SA2.1 answering “how do you know?” questions with reasonable answers.

The student demonstrates an understanding of the interactions between matter and energy and the effects of these interactions on systems by
[3] SB3.1 recognizing that temperature changes cause changes in phases of substances (e.g., ice changing to liquid, water changing to water vapor, and vice versa)

The student demonstrates an understanding of geochemical cycles by:  
[3] SD1.2 describing the water cycle to show that water circulates through the crust, oceans, and atmosphere of Earth.

The student demonstrates an understanding of the forces that shape Earth by:  
[3] SD2.1 identifying and comparing a variety of Earth’s land features (i.e., rivers,deltas, lakes, glaciers, mountains, valleys, and islands).

The student demonstrates an understanding of how to integrate scientific knowledge and technology to address problems by:
[3] SE1.1 identifying local problems and discussing solutions. (L)

The student demonstrates an understanding that advancements in science depend on curiosity, creativity, imagination, and a broad knowledge base by:
[3] SG4.1 asking questions about the natural world.

4th Grade GLEs Addressed:

The student demonstrates an understanding of the processes of science by

[4] SA1.1 asking questions, predicting, observing, describing, measuring, classifying, making generalizations, inferring, and communicating.*

[4] SA1.2 observing, measuring, and collecting data from explorations and using this information to classify, predict, and communicate.

The student demonstrates an understanding of the attitudes and approaches to scientific inquiry by
[4] SA2.1 supporting the student’s own ideas with observations and peer review. (L)

The student demonstrates an understanding of the interactions between matter and energy and the effects of these interactions on systems by
[4] SB3.1 explaining that temperature changes causechanges in phases of substances (e.g., ice changing to liquid water and liquid water to water vapor).