Activity 11: Modeling Interconnected Systems

This activity is intended for a middle school science course. Materials presented here are designed to be implemented in a remote learning environment, either as part of an entirely online or hybrid course.

Students do not need any background information to complete this activity.

This activity is designed to be followed by Activity 12 which allows students to select a product of their choice and reinforce the systems thinking practices introduced in this activity. Activities 11, 12, and 13 are designed to be taught in conjunction to introduce students to systems contributing to water usage and water stress in the United States and prompt students to generate solutions to water stress based on their systems analysis.

• Students are introduced to a simplified agricultural production and supply system.
• Students use structured brainstorming to identify ways water is used in the systems that produce an apple.

Materials:

• Zoom meeting or other online platform (with breakout groups enabled)
• Activity 11 Google Drive Folder:
  • Instructor Guide Activity 11
    • Make a single copy for instructor use
  • Brainstorm Water in Systems Powerpoint
    • Make a single copy for instructor use
  • Class Brainstorm List
    • Make a single copy for instructor use and give students access to view
  • Example Class Brainstorm List
    • Make a single copy for instructor use
  • Student Handout Activity 11
    • Give students access to their own copies to fill out individually
  • Answer Key Student Handout Activity 11
    • Make a single copy for instructor use

Activity Description (total time: 40 min)

Part 1 - Background Information (5 min)

The instructor asks students to open the Student Handout Activity 11 and view Part 1. Part 1 contains a pie chart showing the percent of the total US water usage for each sector of the economy. Students then read the descriptions and examples of how water is used in each of those sectors. Students answer Question 1 based on the chart: which two parts of the economy use the most water?

• The instructor can ask students to complete part 1 prior to class.

Part 2 - Predictions(10 min)

The instructor begins sharing the Water Systems powerpoint. Slide 1 introduces the prediction prompt. Students move onto Part 2 of their handout and predict how much water is used to produce a series of common items and how much water the average person uses in their home each day. 

• The instructor can ask students to complete the predictions of part 2 prior to class.

The instructor uses slides 2-7 to reveal the volume of water used to produce each item on the list: apple, small cheese pizza, hamburger, cotton t-shirt, cell phone, and home use. In addition to revealing the volume of water, the slides include a contextual representation of the volume of water used: the number of microwaves (25 L) full of water needed to produce the item. 

Slide 8 provides citations of the sources used to determine the volume of water used to produce the various items. The instructor can 

Part 3 - Water use in a simple product(20 min)

Part 3 walks students through the process of thinking in systems to create a diagram of the ways water is used to produce an apple.

Slide 9 introduces the question, "What could possibly be using all that water?" to prompt students to think about why so much water is needed to produce the items in Part 1. The two goals for the rest of the activity are also introduced: 

1. Understand a simplified food production and supply system. 
2. Identify how water is used at each step of the production and supply system.

Using slide 11, the instructor tells students they will start by looking at a simple item: an apple. Then, in slide 12, the instructor introduces the question that the apple production and supply diagram answers: How does an apple start from a seed and get to our mouths?

The instructor uses slides 13-16 to explain three different steps in the production and supply system of an apple. Here's an example of what the instructor might say:

• Step 1 (Slide 13): Apple Production (how the apple is grown and stored)
• Step 2 (Slide 14): Apple Supply (how the apple is transported and sold)
• Step 3 (Slide 15): Apple Consumption (we eat the apple)
• Overview of the apple production and supply system (slide 16)
• Here's an example of how the instructor might use these slides: 

"(Slide 13) To answer this question we're going to break down the question into three different steps. The first step is the apple production system. In this step the apple seed starts in the soil. Over several years the seed grows into a tree and begins to produce apples. People then pick the apples and store them in a large refrigerated warehouse. (Slide 14) Next, the apples enter the supply system in which they are transported and sold. People sort and load the apples in the refrigerated warehouse into a truck to be transported. This particular diagram assumes that the apples are shipped with trucks. How else might apples be shipped around the country or to other countries? Once the apples have been transported, if they are going to a grocery store they might go directly to the grocery store to be bought by shoppers who take the apples back to their homes and maybe refrigerators. If they are going to a big institution like our school, they might first be transported to a large food service warehouse where the apples are again sorted and loaded into a different truck. Finally the apples get sent to our school cafeteria which put them in refrigerators or out in bowls for us to purchase. Then finally in step three we eat the apples! The apples made a long journey to get from a seed to your mouth, right?"

Next the class will work together to identify how water is used throughout the apple production and supply system. Slide 17 indicates that the class is moving onto the second activity goal: Identify how water is used at each step of the production and supply system.

Slide 18 introduces the layers of connections that students will use to structure their brainstorming about how water is used at each step in the production and supply systems. 

Slide 19: The instructor explains the three layers of connections with a concentric circle diagram, then follows the loopy link on the Powerpoint and, as a class, the students practice using the three layers of connections to brainstorm how water is used in the apple production system. The instructor can also take this opportunity to introduce students to LOOPY and model how they will create their own LOOPY diagrams in Activity 12.

• An example of a completed class LOOPY, color coordinated to represent the three layers of connections. 

Slide 20: The instructor assigns students to breakout groups of 2-4 students to identify how water is used throughout the supply system. The instructor asks students to only identify water use in the school supply system branch of the diagram. Students should use the same three layers of connections (included on the handout) to structure their group brainstorm.

After 5 minutes, the instructor brings students out of the breakout groups. Using slide 21, the instructor asks each group to share some of the water uses they brainstormed. While the students are explaining the water uses, the instructor creates a new screen share of the Apple Water System google doc linked at the bottom of slide 21 and builds a list of the students' ideas. After soliciting the students ideas, the instructor asks if students thought of any other water uses after hearing their peers ideas. The instructor continues to add ideas to the list for about 5 minutes. 

• An example list of student solicited ideas can be found here.

Part 4 - Prediction and Reflection(5 min)

Slides 22 and 23 ask students to think more deeply about how water might be used to produce processed goods from raw agricultural ingredients. Students may need brief explanations of the production processes of cheese, bread, and cotton t-shirts in order for them to answer these questions.

These prediction questions are intended to tie the initial predictions back into the activity as well as provide a link to Activity 12 in which students map the water use for a processed product of their choice that uses 2 - 3 raw materials or part of the production process occurs overseas.

Slide 22: The instructor prompts students to predict why less water is used to produce an apple as compared to a small cheese pizza, hamburger, and cotton t-shirt. 

• Answers: The items are larger (although this isn't enough to account for all the difference), the items are more processed (there are more steps where people and machines are involved that use water, there are more places that the items have to be transported), the processes involve more wastewater which must be diluted in order to be released back to the environment

Slide 23: The instructor then prompts students to think more deeply: Why does a cheese pizza use less water than a hamburger or a cotton t-shirt?

• Answers: More water is required to raise meat because one cow is only used once, and you have to feed the whole cow. Less water is required to produce cheese because one cow can produce lots of milk to create cheese. Cotton is a crop that uses more water than most plants and the processing process to turn cotton into a t-shirt is more intensive than meat or cheese processing (requires more energy. 

To provide local/classroom context when revealing how much water is used to produce each of the common goods, the instructor could:

• Provide a more concrete visual representation by measuring the volume of an item in the classroom (a desk, the entire classroom, or sink) and explaining how many, or what fraction, of the item would be filled with water to create each item.
• Use the sources on slide 8 to find more course or class-demographic specific items.
• Use the volume of a local reservoir as an additional reference volume. The instructor explains how much of the reservoir would be used in order to make each item. Contact the local water utilities provider if no reservoir/aquifer volume information is available online.

If students have completed the feedback loop activities (Activities 9 and 10), the instructor can model an example feedback loop and/or prompt students to incorporate feedback loops in the class apple production system diagram. The example apple production system LOOPY contains an example of a reinforcing feedback loop of plants releasing water to the atmosphere through evapotranspiration, requiring more irrigation, and then continuing to emit that moisture back into the atmosphere. Another part of this feedback loop could be soil percolation that allows the water to leave the soil and enter the groundwater. Other feedback loops could be:

• Farms using pesticides, the pesticides getting on the farmers, the farmers having to shower more often and use more water.
• Farms depleting the soil by not picking all the apples or not allowing organic matter to return to the soil or overuse of the land, using pesticides/manufactured fertilizers to counter balance that, depleting the soil more, using more pesticides, which in turn require more water to be produced.
• Or oppositely to the two prior examples, farms using regenerative farming practices to reduce the amount of irrigation and pesticide/manufactured fertilizers needed.

Many of these water uses may be foreign to the students. One way to provide explanations of how different products are made, before asking students why certain items require more or less water to be produced, could be to play these two videos: 

Milking Cows/Cow Feed lots (watch to minute 2:00)

• The instructor might draw the connection to cheese pizzas and hamburgers by explaining that the milk will then be turned into cheese or that cows are fed similarly for beef production but live shorter lives. 

Cotton T-shirt Production (4:41 minutes long)

• This video is more holistic than the milk video, showing how a t-shirt is made from farm to factory. 

Alternatively, the instructor should add pictures to the powerpoint, showing what each step looks like. This will allow the students to better visualize the food production and supply system. 

• Seed in the soil
• Young tree
• Apples on a tree
• Farm workers picking apples
• Refrigerated warehouse
• Apples in a truck 
• Apples in a food service warehouse
• Apples boxed in a truck
• Apples in a school cafeteria
• Student eating an apple

This activity could be coupled with a plant biology or earth science soil unit. The instructor could send home a seed and soil so students experience how water is used to grow their seed, then they could map out how they might send the product of the seed (the plant, carrot, bean, etc.) to someone across the country (or to another country). The student can assess how water would be used in the packaging and transportation process.

Answer Key Student Handout Activity 11

This systems thinking module is based on the undergraduate Systems Thinking module on InTeGrate, created by Lisa A. Gilbert, Deborah S. Gross & Karl J. Kreutz. This feedback loop activity relates to Unit 3: Modeling a System.

Online Feedback Loop Diagramming Tool: Loopy by Nicky Case: https://ncase.me/loopy/

Background on US Agricultural Systems for Instructors: A Framework for Assessing Effects of the Food System

Background on Changes in Water Resource Availability and Connection to Climate Change (See Ch. 3): "Chapter 3: Water Resources." Climate Change Impacts in the United States: The Third National Climate Assessment. 2014.

Systems Thinking Vocabulary Glossary

Why teach systems thinking in Middle School?

"Appendix G - Crosscutting Concepts." 2013. Next Generation Science Standards. https://www.nextgenscience.org/sites/default/files/Appendix%20G%20-%20Crosscutting%20Concepts%20FINAL%20edited%204.10.13.pdf

Learn about why we should teach Systems Thinking in Earth Science:

• Lisa A. Gilbert, Deborah S. Gross & Karl J. Kreutz (2019): Developing undergraduate students' systems thinking skills with an InTeGrate module, Journal of Geoscience Education, https://doi.org/10.1080/10899995.2018.1529469
• SERC's page on Complex Earth Systems: An explanation of the different types of  systems thinking involved in Earth's systems 

Learn more about teaching systems thinking: 

• Q Design Pack Systems Thinking. Institute of Play. http://educators.brainpop.com/wp-content/uploads/2014/07/IOP_QDesignPack_SystemsThinking_1.0.pdf
• Mambrey, Sophia, Justin Timm, Jana Julia Landskron, and Philipp Schmiemann. 2020. "The Impact of System Specifics on Systems Thinking." Journal of Research in Science Teaching, July, tea.21649. https://doi.org/10.1002/tea.21649

Learn more about systems thinking:

• Meadows, Donella H., and Diana Wright. 2008. Thinking in Systems: A Primer. White River Junction, Vt: Chelsea Green Pub. https://wtf.tw/ref/meadows.pdf