Have you ever seen a cat catch a mouse? Have you wondered why cats chase mice or pounce on a bird? These are two examples of energy flow in ecosystems, which can be represented in food webs. Energy flow through living systems keeps the organisms and system alive, thus, it is an important core idea for elementary students to conceptualize and apply.

Animals depend on their surroundings for their survival. Some eat other animals while some eat plants. In consuming their food, animals are consuming energy. This cycling of matter and the accompanying flow of energy within an ecosystem occurs because of interactions among and between organisms. The health of an ecosystem is very much dependent on the success and stability of the living things within that ecosystem. Energy needs to flow continuously through all living systems for life to continue, as each component plays a critical role. Disruptions to one component can have significant effects on the entire system. Requiring students to model these relationships through simulations can provide them with a solid foundation for conceptualizing the dynamics and the importance of energy and matter flow among living systems.

To guide students in modeling how ecosystems function, we share “Ecosystem Chess,” a game upper elementary students can play with limited materials to simulate an ecosystem. This game addresses Next Generation Science Standards (NGSS) 5-LS2A and 5-LS2B, in which students “explore interdependent relationships in ecosystems” and the “cycles of matter and energy transfer in ecosystems.” In doing so, students explore the practice of modeling and the crosscutting concept of systems and system models described within the standard. While 5-LS2 directly mentions matter and not energy, because of the tight relationship between matter and energy across science disciplines, Ecosystem Chess provides the added benefit of addressing both concepts. Thus, Ecosystem Chess incorporates the NGSS crosscutting concept of “energy and matter” in which students trace how “energy and matter flows, into, out of, and within systems [and] helps one understand their system’s behavior” (NGSS Lead States 2013). In this article we outline the details of the game and provide information for teacher preparation and implementation. In addition, we suggest lines of teacher questioning to use when playing the game to help scaffold student thinking and conversation. Teachers might start with these suggestions and further refine them over time through reflective practice to meet the specific needs of their students. This game can be a single lesson or part of a larger lesson and series of simulations for students to explore. Because it lends itself to a wide range of environments, teachers are encouraged to engage the game multiple times as they support students in learning about the roles of various groups in an ecosystem, energy transfer, and human impacts within the ecosystem. Ecosystem chess is very open ended by design to support teachers in the widest range of settings and circumstances.

Overview of Ecosystem Chess

Ecosystem chess engages students in modeling and exploring the relationships between different members of an ecosystem. After teachers give a lesson on food webs, illustrating the ways that matter and energy move throughout an ecosystem, teachers can engage students in game play that models these relationships. To play, students are assigned a role within an ecosystem either as a producer, consumer or predator. Once assigned, students will move around a classroom chessboard interacting with each other based on their role within the ecosystem. When members of the ecosystem meet on the board, they “battle.” Success is determined based on who occupies the higher role on the food chain. Ecosystem Chess focuses students’ attention on the movement of energy within and throughout an ecosystem (5-LS2-1) because when one organism competes with the other—one is consumed and the energy and matter from the organism that is eaten is transferred to the consumer. This game can be played to model any ecosystem! The game acts as an in-class simulation where students physically act out and model the interrelationships of an ecosystem. Students access these concepts through engaging and reinforcing psychomotor interactions that build connections between their decisions and actions and the scientific content. This simulation is specifically designed to allow students to explore the interactions of different components of an ecosystem and the flows of energy and matter within it. Teachers can tailor the complexity of the ecosystem to the skills and ages of their students.

Introduction to Ecosystems

Begin the lesson by introducing students to an observable natural phenomenon by watching a video of a weasel chasing a rabbit (see Online Resources). Ask students to imagine they are the rabbit, “How do you get the energy to run and hop away?” Now ask the students to imagine they are a hungry weasel, “How will you get energy to chase down the rabbit?” Allow your students to share their ideas with a neighbor before sharing with the class. Students often respond with an understanding of animals eating to get their energy. They share ideas consistent with bunnies eating grass and plants but are often not aware weasels are omnivores that will eat rabbits. Encourage students to share their thoughts, but do not introduce new vocabulary or concepts. Next, direct students to draw their initial model of the observed phenomenon in their science journal or student handout (see Supplemental Resources). Ask students, “Where do animals in an ecosystem get their energy?” Direct students to draw their model using arrows and words to explain the phenomenon. Ask students to show their model to their seat neighbor and explain where the animals in this ecosystem get their energy and what they do with it. Explain to students that after the class models the energy transfers in an ecosystem by playing the game, you will return to their initial models and add any additional information that will help better explain the phenomenon.

Game Preparation

Teachers must make a classroom chessboard and Ecosystem Chess player cards in advance. The board is made by taping squares on the floor of the classroom (or any open space) with masking tape. The squares should be big enough for a student to stand inside (approximately 2’×2’). For a typical class of 30 students, you would want a 6×6 (36 squares) or greater board to allow students to move around. Students can move in any direction when their ecosystem level is called on to move. Before making the game cards, first identify common organisms in your biome of choice. Within our ecosystem, we use plants, mice, rabbits, coyotes, hawks, and snakes for our players’ roles. The plants are the producers, creating their own food with the help of the Sun. They take solar energy and convert it into consumable energy through photosynthesis. Typically, ecosystems have many more producers than they have consumers because a great deal of energy is lost through the consumption process. It is important to note that students can often forget that the law of conservation of energy states that energy cannot be destroyed. Rather, energy is lost through the trophic levels by the animals’ metabolism, mostly by producing heat. Consumers are animals that consume or eat producers or other consumers. These layers of consumption and energy transfer are called trophic levels within an ecosystem. For our example, the ecosystem’s producers are consumed by a network of primary consumers such as mice and rabbits. Once again, not all the energy consumed moves from the producers to primary consumers due to heat transfer. After the primary consumers eat the producers, the secondary consumers eat the primary consumers. Secondary consumers are also called predators. It’s important to note that when one organism eats another, matter and energy are transferred to the consumer. For the purposes of this game, teachers can choose whether they address trophic levels or engage students more simply around the loss of energy between consumers and producers.

To create the game player cards, write the name of each ecosystem member on the front of an index card. Below the name, write the level the organism occupies in the food web (i.e., producer, primary consumer or secondary consumer/predator), who eats that member of the ecosystem, and who they eat (see Figure 1). For more complexity, cards can also state how many turns each ecosystem member can go without “eating” before being out of the game. Teachers want to ensure they have many more members of the producers and primary consumers than the secondary consumers so that they can use the student movements and game to simulate the changes in the ecosystem. For a typical class of 30 students, a good ratio between producers and consumer levels is 3:1. That means a class would have 17 producers, five or six primary consumers, and two secondary consumers/predators.

Playing the Game

Once students have their cards, they should be instructed to keep their ecosystem identity hidden and take a position on the chess board. Then the teacher asks the students to move, in turn, around the board (see Figure 2). Each student gets to choose to move a square or not. If two students end up in the same square, they must show each other their cards (see Figure 3). Predators or secondary consumers “eat” primary consumers, who “eat” producers. Once a student meets something higher up the food chain, they are out. When a player meets another player that has the same role or an equivalent level, the two players lose their turn but remain in the game. Game play continues until there are only a few players left. Then students and teachers can calculate the number of each member group that are left. Teachers should then lead a discussion with their class on what happened and what factors affected each group of organism’s success or failure. The game can be played multiple times with the teacher changing variables to affect game play and deepen students’ thinking. One such change would be to include humans in the ecosystem and see how they might change the game. Another example of a change would be to have a blight of crops, which eliminates most of the producers. By changing the ecosystem and the variables at play, students can begin to engage in predicting how changes in the ecosystem affect the exchange of energy across levels.

Concluding the Lesson

Once the game and class discussion are finished, direct students to revise their initial model of the phenomenon. Where do organisms in an ecosystem get their energy? You may choose to show the phenomenon video again. Direct students to draw their new model with their understanding of energy transfer after playing the game. Their revised models should include the additional organisms from the game and their relationships. Ask students to reflect on the differences between their initial and revised models. How did your understanding of energy transfer in an ecosystem change? How was matter transferred in the ecosystem? What did you draw differently? What do you know now that you didn’t know before? These questions will allow students to reflect on the knowledge they brought into the class and how their thinking has changed after modeling matter and energy transfers by playing Ecosystem Chess. Encourage students to share their model with a seat neighbor to explain how matter and energy transfers in an ecosystem. Teachers may choose to use the student’s post model as an assessment tool.

Differentiation

To support English Language Learners (ELLs) and students who struggle with reading in English, we recommend the following: (a) include images of the organisms on the game cards; (b) consider using color-coded dot stickers for each role (e.g., green dot on producer cards); (c) model what students will do in the game by projecting an image of two cards and physically showing what would happen if these two cards meet; (d) assign students to work in selectively designed pairs to navigate the board as needed (e.g., visually impaired student with a friend, or two bilingual students who share another language); (e) use selective pairing, encouragement for home language use in writing and speaking, and a think-pair-share format to further facilitate ELL students’ participation in the initial and final modeling tasks and whole-class discussions; and (f) translate key question prompts into students’ home languages and/or pre-plan ways to communicate these questions using images and gestures.

Benefits of a Game-Based Approach

Gaming and simulations are established ways to engage students in playful learning (Kafai and Burke 2015). By engaging students in learning about ecosystems and trophic levels through this game-based simulation, you can scaffold their learning within a context that is both visible and engaging. Furthermore, because the game can be tailored to the needs and level of students, there are a wide number of ways to differentiate the lesson for students. To enhance conceptual transfer, consider repeating the game with an unfamiliar ecosystem such an ocean, lake, or arctic.

Supplemental Resources

Download the journal/handout template at https://bit.ly/3j1uXWW.

Online Resources

High Speed Rabbit Chase: www.youtube.com/watch?v=zHLju_nwPJc

Colby Tofel-Grehl (colby.tg@usu.edu) is an associate professor, and Sarah Braden is an assistant professor, both at Utah State University in Logan, Utah. Candace Penrod is a doctoral student at Utah State University and science supervisor for Salt Lake City School district. Laura Wheeler is a doctoral candidate at Utah State University. Tyler Hansen is a doctoral student at Utah State University and a science teacher in Cache Country School District. Andrew Jones is a doctoral student at Utah State University and science specialist for Canyons District. Clayton Chamberlain is a doctoral student at Utah State University and a Curriculum Architect for Studies Weekly.