Science · Grade 7

Active learning ideas

Biotic Limiting Factors: Competition & Predation

Active learning helps students grasp biotic limiting factors because competition and predation are dynamic processes best understood through firsthand experience. Movement-based simulations and role-playing create visceral memories of population regulation, making abstract concepts tangible for learners who struggle with static examples.

• Ontario Curriculum Expectations
• MS-LS2-1

• 35–50 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Simulation Game
• 45 min · Pairs

Simulation Game: Predator-Prey Chase

Scatter 100 beans (prey) on the floor; pairs act as predators collecting beans in 1-minute rounds while 'prey' decreases each round. Graph population changes over 10 rounds. Discuss how predation limits prey growth.

Differentiate between interspecific and intraspecific competition.

Facilitation Tip

During the Predator-Prey Chase, adjust the playing field size or starting prey/predator ratios to match your class size, ensuring no student waits too long between turns.

What to look for

Present students with two scenarios: 1) Squirrels competing for acorns in a forest, and 2) A fox hunting rabbits. Ask students to identify which scenario represents intraspecific competition and which represents interspecific competition, and to justify their answers.

• Apply
• Analyze
• Evaluate
• Create
• Social Awareness
• Decision-Making

Activity 02

• Stations Rotation
• 50 min · Small Groups

Stations Rotation: Competition Scenarios

Set up stations with limited resources: food bowls for intraspecific (same animal cutouts), territory maps for interspecific (different species). Small groups compete, record winners, and rotate. Compare outcomes in class share-out.

Analyze how predator-prey relationships regulate population sizes.

Facilitation Tip

For the Station Rotation, assign each group a scenario card with clear roles and resources, then circulate to ask probing questions like 'What would happen if one competitor left the area?'

What to look for

Pose the question: 'Imagine a new, highly effective predator is introduced to an area with rabbits and foxes. What are two possible outcomes for the rabbit population and two possible outcomes for the fox population? Explain your reasoning.' Facilitate a class discussion on their predictions.

• Remember
• Understand
• Apply
• Analyze
• Self-Management
• Relationship Skills

Activity 03

• Case Study Analysis
• 35 min · Individual

Data Analysis: Lynx-Hare Graphs

Provide historical population graphs; individuals plot trends, identify cycles, and predict effects of removing predators. Pairs present predictions with evidence from data.

Predict the long-term effects of introducing a new predator into an ecosystem.

Facilitation Tip

When analyzing the Lynx-Hare graphs, provide colored pencils and have students trace the peaks and valleys together, labeling each phase to reinforce the cyclical nature of population changes.

What to look for

Ask students to draw a simple diagram illustrating a predator-prey relationship. They should label the predator and prey and write one sentence explaining how this interaction affects the population size of the prey.

• Analyze
• Evaluate
• Create
• Decision-Making
• Self-Management

Activity 04

• Case Study Analysis
• 40 min · Whole Class

Role-Play: New Predator Introduction

Whole class divides into prey, original predators, and new predators. Simulate hunts over rounds, adjusting numbers based on 'success.' Debrief on ecosystem changes.

Differentiate between interspecific and intraspecific competition.

Facilitation Tip

In the New Predator Introduction role-play, give students five minutes to prepare arguments for or against the predator’s introduction, then guide a structured debate to surface multiple perspectives.

What to look for

Present students with two scenarios: 1) Squirrels competing for acorns in a forest, and 2) A fox hunting rabbits. Ask students to identify which scenario represents intraspecific competition and which represents interspecific competition, and to justify their answers.

• Analyze
• Evaluate
• Create
• Decision-Making
• Self-Management

A few notes on teaching this unit

Teachers should begin with simple, low-stakes simulations to build intuition before introducing mathematical models. Avoid overwhelming students with jargon; instead, use terms like 'crowding' or 'chase' during activities, then connect these experiences to scientific vocabulary afterward. Research shows that students retain predator-prey dynamics better when they physically embody the roles, so prioritize movement and repetition over static lectures.

Successful learning looks like students accurately distinguishing intraspecific from interspecific competition, explaining predator-prey cycles using evidence from simulations, and predicting ecosystem impacts when new species are introduced. Small-group discussions should reveal growing confidence in applying these concepts to unfamiliar scenarios.

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Watch Out for These Misconceptions

• During the Station Rotation, watch for students who assume competition only happens between different species when observing their assigned scenarios.

  Redirect their attention to the identical 'animals' in their group and ask, 'What happens to your food pile when more of your own species arrive?' to highlight intraspecific competition.

• During the Predator-Prey Chase, watch for students who believe predator populations always outnumber prey.

  Pause the game and have students count the remaining prey and predators, then ask, 'Why do you think the prey numbers dropped so low?' to reveal the cyclical relationship.

• During the New Predator Introduction role-play, watch for students who assume adding any predator will stabilize the ecosystem.

  Ask groups to present their predicted outcomes, then challenge them with, 'What if this predator also competes with the fox for shelter?' to uncover unintended interactions.

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Methods used in this brief

• Simulation Game
• Stations Rotation
• Case Study Analysis