Grade Level: 6-8
Subjects: Science, Language Arts, Visual Arts
Duration: 90 minutes
Learning Objectives
By the end of this lesson, students will be able to:
- Define and differentiate between producers, consumers, and decomposers.
- Explain how energy moves through a food chain and food web.
- Identify types of species interactions (predation, competition, mutualism, commensalism, parasitism).
- Create and present their own local ecosystem food web.
Materials
- Chart paper or poster board
- Markers/coloured pencils
- Scissors and glue
- Printed or digital photos of local species (optional)
- Internet access for research (iNaturalist or local conservation authority websites)
- Food web cards (teacher can provide a set of local species names with short descriptions)
Curriculum Connections
- Science: Ecosystems and interactions within them.
- Language Arts: Communicate information clearly using scientific vocabulary.
- Visual Arts: Use visual representation to convey ideas about nature and relationships.
Terms
- Producer: A plant or algae that makes its own food using sunlight through photosynthesis.
- Consumer: An organism that eats other organisms to get energy.
- Herbivore: Eats only plants. (Example: Beaver)
- Carnivore: Eats only other animals. (Example: Fox)
- Omnivore: Eats both plants and animals. (Example: Bear)
- Decomposer: An organism, like fungi or worms, that breaks down dead plants and animals, returning nutrients to the soil.
- Food Chain: A sequence that shows how energy moves from one organism to another through eating.
- Food Web: A network of many food chains in an ecosystem showing all the feeding relationships.
- Energy Flow: The movement of energy from producers to consumers and decomposers in an ecosystem.
Instructions
Introduction
Begin with the question: What happens if one species disappears from an ecosystem?
Show a short clip or images of local ecosystems.
Lead a short discussion: How are these organisms connected?
Explore
Review key concepts together from the list of definitions.
Create a quick class energy chain – assign students roles (sun, grass, hare, fox, etc.) and have them pass a spool of string or yarn to represent the flow of energy.
Apply – Build Your Local Food Web
Students work in small groups to design a food web of a local ecosystem.
Choose a local habitat (forest, pond, grassland, backyard, coastline, etc.).
Identify at least 8-10 species found in that habitat.
Research their diet and interactions (e.g., who eats whom, who competes, who helps).
Draw or digitally map their food web, showing arrows for the flow of energy.
Label any special relationships (e.g., mutualism between bees and flowers).
Bonus: Have students include one human interaction – e.g., pollution, habitat change, conservation efforts – and explain how it affects the web.
Share and Discuss
Each group presents their food web and shares:
- One interesting interaction they discovered
- One potential consequence if a species disappeared
- What role humans play in their ecosystem
Reflect
Students answer:
- What was the most surprising connection you discovered in your food web?
- Why is biodiversity important to the stability of ecosystems?
- How are all systems are interconnected including energy, species, and people?
Extensions
- Art: Create a mural or digital collage of the local ecosystem, demonstrating the interconnected food web.
- Technology Integration: Use an online tool like Google Drawings or Canva to create interactive food web posters.
