Lesson 1 – Introduction to Systems and Models

This is the first lesson of the Systems Are Everywhere Module. In this lesson, students will be introduced to systems and systems modeling. Every day we face complex problems related to health and medicine, nutrition and agriculture, the environment, social justice, and many other important topics. To improve understanding, make choices, and take action we must understand the parts, connections, and dynamics of the systems all around us.



COURSE: Any science / STEM course that uses systems. Examples of courses where this has been used are: Physical Science, Life Science, Biological Science, Environment Science, Physics, Chemistry, Biology, Oceanography, Engineering, Economics, Mathematics, General Elementary Education.

UNIT: Units that include applications of cycles, feedback loops, circuits, processes, equilibrium, homeostasis, or response for any STEM content. Additionally, units that focus on building 21st-century skills, “soft skills”, problem-solving, design thinking, systems thinking, career connections, career awareness, and career development skills. Systems models have dimensionality that can be used to represent math variables in a visual way, therefore the activities in this lesson can be integrated into courses requiring math and mathematical thinking.

OBJECTIVES: See the Standards Addressed page for information about the published standards and process we use when aligning lessons with NGSS and other Science, Math, Literacy and 21st Century skills). In addition to the aligned objectives listed in buttons on the upper-left of this page and in the table below, for this lesson, here is a breakdown of:

What Students Learn:
  • A system is a collection of interconnected and interdependent parts.
  • Systems can be found in all aspects of life, and can be simple or complex.
  • Modeling systems provides insight into the relationships and contributions of each part of a system.
  • Computer modeling tools allow for the visualization of the flow of information in a system.
  • A systems model includes nodes to represent the parts of a system, and edges to represent the relationships between those parts.
  • Systems generally have mechanisms for balancing growth and stability.
  • Change in a systems model can be positive, negative, or neutral.


What Students Do:
  • Students evaluate a list of items to determine whether they are a system.
  • Students explain what a system is.
  • Students build understanding of real-world systems by analyzing parts of an urban farm system.
  • Students use an online tool, Loopy, to model a subsystem of the urban farm.
  • Students build on their Loopy model to generate ideas for mitigating the negative effects and / or elaborate on impacts to the system
Aligned Next Generation Science Standards
All three dimensions of the Next Generation Science Standards are addressed in this lesson. Please note that based on what part of this lesson you emphasize with students, you will cover different NGSS to different levels. Based on what is possible, we have listed here and in the buttons on the left the NGSS that are make the most sense to integrate and emphasize with this content.

Performance expectation: 

HS-ESS3-4 Evaluate or refine a technological solution that reduces impacts of human activities on natural systems.* (LS2.C)

HS-LS2-5 Ecosystems; Interactions, Energy and Dynamics. (Develop a model to illustrate the role of photosynthesis and cellular respiration in the cycling of carbon among the biosphere, atmosphere, hydrosphere and geosphere;* This PE can be addressed if the students thoroughly include the role of the farming process (photosynthesis, etc.)

HS-ESS2-4 Earth’s Systems. Use a model to show how variations in the flow of energy into and out of Earth’s systems result in changes in climate*.

Can meet these performance expectations, depending on course content and depth of phenomenon systems modeling).

The bundle of performance expectations above focuses on the following elements from the K-12 Science Education Framework:

Highlighted Science and Engineering Practice(s)

Highlighted Disciplinary Core Idea(s)

Highlighted Crosscutting Concept(s)

SEP-1: Asking Questions and Defining Problems

SEP-2: Developing and Using Models

SEP-8: Obtaining, Evaluating, and Communicating Information.

HS-ESS3.C: Human impacts on earth systems.

*LS2.C: Ecosystem Dynamics, Functioning, and Resilience

*HS.ESS2.D: Weather and Climate

Influence of Engineering, Technology and Science on society and the natural world

CCC-4: Systems and System Models

CCC-2: Cause and Effect

*CCC-5: Energy and Matter

CCC-7: Stability and Change

Systems Thinking Skills: Systems thinking developed through this lesson trains students to apply these skills to defining problems, building and testing models with application to all science core subjects. The skills include: Exploring boundaries; Appreciating multiple perspectives;Understanding relationships; Thinking in terms of systems themselves.

Common Core: HSN.Q.A.2: Define appropriate quantities for the purpose of descriptive modeling. (HS-ESS3-4)

21st Century skills and CTE: 1.A Think Creatively; 1.B Work Creatively with Others; 2.A Reason Effectively; 2.B Use Systems Thinking; 2.C Make Judgments and Decisions; 3.A Communicate Clearly; 3.B Collaborate with Others; 4.A Access and Evaluate Information; 4.B Use and Manage Information; 5.B Create Media Products; 6.A  Apply Technology Effectively;  7.A Adapt to Change; 7.B Be Flexible; 8.C Be Self-Directed Learners; 8.B Work Independently; 9.A Interact Effectively with Others;  10.A Manage Products; 10.B Produce Results; 12.E Environmental Literacy* (*Meets criteria within the scope of lesson 1, 2 and 3 depending on the focus of the chosen systems model).


Pacing Guide: 1, 50-minute class period


Lesson 1 serves to foster students’ understanding of systems and systems models. Students begin by exploring and defining what a system is (Activity 1.1), then learning about and modeling a complex urban farm system (Activity 1.2). To model the system students apply their knowledge of systems to brainstorm the parts and connections of the system, then use an online tool (Loopy) to model the interactions of those parts and connections. Lastly, students work in groups to build on the model by brainstorming ways to mitigate the negative effects of the system and / or elaborate on impacts to the system.

The urban farm example is used to provide context for how systems approaches are used in real life to address complex problems, as well as to introduce students to diverse STEM careers and workplaces. Additional activities are suggested for more career connections related to the activities in this lesson (see the Career Connections section).



There are no prerequisites for Lesson 1.



Teacher & student internet access & online conferencing tools…
  • While this lesson can be delivered in-person, it was developed intentionally to be delivered as a remote learning experience. Therefore if leading remotely, students and educators should have access to and familiarity with using video conferencing tools (Zoom, teams, Google Meet, etc.) including using chat, sharing screens, and breakout rooms. We also suggest using online collaborative tools (Google Docs, Google Slides, OneNote, Jamboard, etc.) to share ideas and brainstorm. These may require you to request access from your IT specialist or administrator. We have only suggested tools that are free and have been accessed by other schools and districts.
Safety Protocols…
  • The lesson includes use of breakout rooms for small group collaboration. Follow your district’s policies for using and managing breakout rooms with students.
  • The lesson includes students sharing their screen to share their models and presentations with the class. If screen sharing is not allowed, students can share a link to their model or presentations with you and you can share for them.
Media and video clips…
Print outs or digital copy…



The following instructions outline steps for leading each activity as well as suggested speaker notes (in italics) and background information. Speaker notes have also been added to the presentation slide notes when applicable.

Pre-Assessment (10 minutes)

Prior to starting the unit have students complete the Unit Assessment. This can be done on paper or questions can be added to an online form, such as Google Forms. Allow 5-10 minutes for students to complete the assessment. The pre-assessment will allow you to gather evidence of students’ readiness before beginning the unit. This evidence can help you identify and meet learners’ needs. Students will take the Unit Assessment again at the end of the unit. Comparison of the Pre and Post-Unit Assessments can provide you with evidence of student learning and engagement with the unit. The Pre and Post Unit Assessments can also be shared with students as a means for them to reflect on their learning.

Activity 1.1: What is a system? (10 – 15 minutes)

In this activity, students begin to define the characteristics of a system.

Present the Lesson 1 presentation

Slide 2: Every day we face complex problems related to health and medicine, nutrition and agriculture, the environment, social justice, and many other important topics. What is an important complex problem you have noticed? (potential student responses: opioid crisis, plastics in the oceans, gun violence, etc.)To address these complex problems we need all members of our society working collaboratively to make informed decisions, design innovative solutions, and to prevent new challenges from arising.  To do this will require collaboration, systems approaches and systems thinking skills. So, what is a system?


Slide 3: Have students complete the “Is it a System?” worksheet. This can be done on paper, or the questions and items listed can be transferred to an online survey or polling tool. You can also post this slide and have students write their answers on paper or annotate the slide if using Zoom. Have students select all the items on the list they think are a system. There is no absolute correct answer; this is just an opportunity for students to start thinking about what a system is. After they have completed that task they should spend a few more minutes writing what they think defines a system, or how they would explain a system to someone else. Once students are finished, assess which items students selected as a system. This can be done by raising hands, or if using online tools, showing survey or poll results, or sharing via a chat box. Point out any items that were selected by only a few or no students. Facilitate a discussion amongst the group about why these items should or should not be selected as a system. This leads into students sharing their definitions of what a system is.


*Note: A system is a group or collection of things or elements (including processes) that are interrelated and interdependent, thus have some influence on one another and the whole (AAAS 1989; Arnold & Wade Procedia CS 2015).  Systems can be manufactured objects (thermometer, bicycle, cell phone, electrical circuit), life-forms (grasshopper, human body, seed, cell), combinations of living and nonliving things (food web, aquarium, ocean, soil, Earth), physical bodies (volcano, Earth and its Moon), processes (water cycle, hurricane, digestion), or quantitative relationships (Density = Mass/Volume, A + B = C, graph). In this list, the only 2 things that most people determine are not a system are the pile of sand and the box of nails because the individual nails don’t influence one another, if you removed one, it would still be a box of nails. Same for the pile of sand.  However, some students will defend that they are. As long as students can justify their answer there is no right or wrong answer.


Slide 4: Summarize for students that systems are made of parts, connections between those parts, and dynamics. This will provide structure for thinking about systems for the remainder of the module.


Activity 1.2: How do systems models help us understand how systems work and how they can be affected? (30 minutes)

In this activity, students learn how models can be used to understand systems, and how to use the online modeling tool, Loopy.

>Continue to present the Lesson 1 presentation


Slide 5: Prepare the students that they are now going to explore a complex system. This is Ray Williams, Managing Director of the Black Farmers Collective in Seattle, WA, and an Urban Farmer.


Slide 6: While watching the video together students should write down the part’s of Ray’s system that they see and/or hear.


Slide 7: Watch the video featuring Ray Williams and the urban farm, Yes Farm. The video is embedded in the presentation, but can also be played on its own @ https://youtu.be/ZMI1zOraNjU


*Note: if you are unable to use the video, you can access a 1-page profile of Yes Farm that contains similar information. If you want to have a deeper discussion on Yes Farm or urban farming in general you can use this 1-page question sheet or the general questions listed in Option 3 of the Career Connections Overview page. Also see suggested activities in the Career Connections section below.


Slide 8: In the video, Ray talks about his goals of engaging the community and affecting change. He also discusses many different parts of his system and the many people and organizations that contribute. After the video students will share the parts that they noticed. This can be done as a think-pair-share in-person, or if you are remote students can add the parts to chat.


*Note: Showcase the complexity of the system by sharing with students your notice of similarities and differences amongst the parts they identified as well as the diversity of the parts.


Slide 9: In the video, Ray talks about engaging with students to build knowledge about systems [1:00 – 1:53]. Continue the discussion with students by asking them “How does identifying the parts of the system help us understand how systems work and how they can be affected?”


*Note: By identifying the parts of a system, we can start thinking about relationships between these parts, and areas we can leverage to better understand how the system works and how to make improvements if they are wanted or needed.


Explain to students that to truly understand relationships and contributions of each part of a system, Ray and other STEM professionals would create a model of their system.


Slide 10: Modeling systems can be a powerful process and tool as we strive to improve understanding, make choices, and take action. To demonstrate that process, today we are going to build a model of one subsystem from Ray’s complex system.


Slide 11: Before we begin that process I want us to think a bit more about the power and limitations of models.  “All models are wrong, but some are useful” is a famous quote by statistician George E.P. Box. Any thoughts on what this quote means?


A model is just a simplified representation of a system. Models always fall short of the complexities of reality but are still useful in helping us create a visual representation of a complex system so we can understand and predict the way the system works. As our knowledge about the system grows so does our model. So in that way models are always changing. This is important to emphasize to students as they begin building systems models.


*Note:You can learn more about this quote and its meaning on Wikipedia. You can read more about models and the importance of models in science and science education in Chapter 6 of  NSTA’s “Helping Students Make Sense of the World Using Next Generation Science & Engineering Practices”, as well as Chapter 6 of “Ambitious Science Teaching” by Windschitl, Thompson and Braaten (2018).


Slide 12: This activity will be composed of two parts. In part 1, I will demonstrate how to use the online modeling tool, Loopy, by modeling part of Ray’s system. In part 2, you will work in small groups to generate ideas and build on the model.


Slide 13: As a reminder, systems include parts, connections between those parts, and dynamics or movement. So when we create a systems model we need to include all of those pieces. 


Slide 14: In our model, we represent the parts as “nodes”, which are depicted as circles. The slide shows 2 of the parts from Ray’s system, traffic and pollution.


Slide 15: Connections and dynamics are represented by edges, which are depicted by lines. And in some cases arrows, if we know the cause and effect relationship between the nodes. In Ray’s system we know that traffic causes pollution, so our arrow goes from traffic, the cause, to pollution, the effect


Slide 16: In our model, we also want to indicate whether a part is adding to or taking away something from the system. This is depicted by “+” and “-” signs over the edges. Since traffic is adding pollution to our system, we add a + sign over the edge.


Slide 17: In contrast, if our model instead was looking at the effects of traffic on our ability to be on time, we would add a minus sign over the edge because traffic is taking away or negating our ability to be on time.


Note: More information about systems and systems modeling can be found on our Computational Modeling module “Introduction to Systems and Modeling


Slide 18: Loopy is an online tool that allows us to create models and easily visualize the dynamics of a system


Systems models can be created on paper, you don’t have to use Loopy. However, Loopy is a fun tool that can easily be integrated into an online learning space. And, in the professional world computational tools eventually become a necessity as models get more and more complex, so using Loopy can be a way to introduce students to professional tools. As you demonstrate how to use Loopy, students can listen, or try Loopy out as you talk. You will want to demonstrate how to create a simple model in 3 steps. You can create your own model or use one of the 3-node models we have developed for you.



Note: There are many tutorials on the Loopy site to help you. You can also refer to the instructions in our other module  ““>Introduction to Loopy – Modeling a Bad Day”


Step 1 – Draw the first 2 nodes with a positive edge connecting them to model the cause and effect relationship. Play the model to demonstrate this relationship.

      • Model 1: traffic -> pollution
      • Model 2: Urban farm -> community


Step 2 – Introduce a phenomena.


Step 3 – Integrate this phenomenon into the model

      • Model 1: To explore the relationship between staying home and our model in Step 1, we are going to add a new “stay home” node. The “stay home” node should be a different color than the “traffic” and “pollution” nodes to depict the addition of a new part into an existing system. Create a new edge to connect “stay home” and “traffic”. Ask the students whether this should be a positive or negative edge and why. It will be a negative edge because staying home causes a reduction in traffic. Once the model is complete show them how to save the model as a short bit.ly link and share the link with them.
      • Model 2: Ray discusses many challenges faced on an urban farm. One of those challenges is people cutting through the fence and trespassing through the gardens. To explore the impacts of these challenges and how their mitigation steps help to address these challenges we are going to add a new “trespassing” node into our model. The “trespassing” node should be a different node to depict the addition of a new part into an existing system. Create a new edge to connect “trespassing” and “Urban farm”. Ask the students whether this should be a positive or negative edge and why. It will be a negative edge because trespassing causes damage to the urban farm. Once the model is complete show them how to save the model as a short bit.ly link and share the link with them.


Slide 19: Now we’re going to put you into breakout groups to build on this model for about 15 minutes. Start by brainstorming with your group what parts you want to build into the model – discuss ways to mitigate the negative effects and / or elaborate on impacts to this system. Choose a “Loopy Leader” who will share their screen and modify the Loopy model based on node and edge suggestions from the group. Be sure to pause periodically to test your model to ensure the dynamics of your model look how you want them to.  When you are done, be sure to save your model as a new bit.ly link, otherwise, the changes will not be saved. When we all come back together, each group will share their bit.ly link and give a brief overview of their model and thought process.

Divide students up into small groups to brainstorm how to add to the Loopy model. They can discuss ways to mitigate the negative effects and / or elaborate on impacts to this system. The main idea is for them to start thinking about connections to this system and to become familiar with using Loopy as a modeling tool. Provide students with at least 15 minutes for this activity. Remind them to save their modified model as a new bit.ly link or they will lose all of their work. Here are some examples of built-out models. These should be used to guide your professional learning, not as “correct” models students should be able to replicate.


Slide 20: Each group will share their model with the class. Members of the group will give a brief overview of their thinking and approach. Give each group 1-3 minutes to present. Allow 1-2 minutes after each presentation for the class to provide positive feedback on what they liked and ways they could incorporate ideas from that model into their own model. Be sure to collect the bit.ly links from each group if you want to review their work in greater detail. You can provide feedback to each group during their presentation or as a follow-up. The feedback should provide students with ideas on ways they could add to the model, or ask more questions on why they chose to model things in a particular way.


Modeling is an iterative process. If time allows, you can have students further develop their model after receiving feedback and seeing other models.

Career Connection

At the end of Lesson 1, your students will be ready for their first Career Connected Activity (CCA). These are called Career Connected Activities because they: 1) highlight STEM careers, and 2) are connected specifically to the learning that took place in the lesson. These activities have been crafted to build awareness (especially for unique STEM careers and pathways), identity and to build “soft” skills such as 21st Century Learning Skills.

To plan for this, first consider how much time you want to devote to this additional content. For each lesson, we offer four options, listed in columns as A-D. You can mix and match the options for each lesson. This means you can have some of these activities take place in class and some out of class (as homework). Based on how much time you have available, choose one section of the career connected activity below. For every one of these four options, prior to beginning the CCA, first recap what your students learned in the lesson they just completed. This will help them internalize the content of the CCA to improve the positive impact of these activities.

What to do if you have this much time available:

A homework / outside of class B 5-10 minutes in class C half of a class period (~25 minutes) D entire class period (~50 minutes)
Have students respond to the questions on this handout for homework. Brainstorm on other careers and workplaces where systems modeling would be used. Brainstorm on careers, college majors, and school courses that could be involved with running an urban farm or involved with one of the collaborators of Yes Farm. This can be done in small groups, with those groups reporting out to the entire class. Students can use the WA STEM Labor Market tool as a resource. In small groups take on the role of an urban farmer. Groups should identify where in their community the garden would be located, the challenges faced in that area and ways to mitigate those challenges, a diagram of the garden layout, the supplies needed, and collaborators to help support this work. Groups will report out to the entire class.


How will I know they know?

A Unit Assessment is provided to summatively assess student learning. We recommend having students take this unit assessment before starting the module (Pre-assessment) and after completing all three lessons of the module (Post-assessment). Comparison of the Pre and Post assessments can be used to demonstrate growth in student learning.

There are several formative assessments that are built within this lesson.  These include the:

  • “Is it a System?” worksheet (which includes options for an online survey, polling, annotations and/or discussion)
  • Notes and discussion around Ray Williams’ video and profile and the Lesson 1 presentation
  • Loopy models created and submitted by individual students and/or groups of students and the group share-out after these are created in breakout rooms

And/or you can formatively assess student learning in these lessons using your choice of exit ticket format. Suggested questions:

      • What did you learn today that surprised you?
      • What are you excited to learn more about?
      • What questions do you have at this point?



ELL students may benefit from a vocabulary list and peer notes that correspond with the module. Also, the videos can be viewed with closed captioning via YouTube.