Biology · 12th Grade

Active learning ideas

Ecological Succession

Ecological succession involves understanding how ecosystems develop over time, which can feel abstract to students if taught as a static sequence. Active learning helps students visualize change and recognize patterns by engaging with real-world examples, making the concept more concrete and memorable.

• Common Core State Standards
• HS-LS2-6

• 20–50 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Gallery Walk
• 35 min · Pairs

Gallery Walk: Before and After Succession Photos

Post paired photo sets around the room showing sites at different succession stages (e.g., Mount St. Helens 1980 vs. 2005 vs. today; old-field succession in the eastern US). Student pairs rotate, recording species present, estimated stage, and key evidence at each station. Groups then share observations and build a class timeline on the board.

Explain how primary succession differs from secondary succession in terms of time and species composition.

Facilitation Tip

During the Gallery Walk, assign small groups to specific photo stations to ensure all students contribute observations and questions.

What to look for

Present students with two scenarios: one describing bare rock exposed by a retreating glacier, and another describing a forest after a wildfire. Ask them to write one sentence for each scenario identifying the type of succession and one sentence explaining why they chose that type.

• Understand
• Apply
• Analyze
• Create
• Relationship Skills
• Social Awareness

Activity 02

• Think-Pair-Share
• 20 min · Pairs

Think-Pair-Share: Pioneer Species Trade-offs

Pose a scenario: a wildfire burns through a forest. Ask students individually to identify three characteristics a pioneer species would need to survive and reproduce first. Pairs compare lists, then the class consolidates a ranked list with reasons. Follow with a brief reading on nitrogen-fixing bacteria in early succession to test their predictions.

Analyze the role of pioneer species in initiating ecological succession.

Facilitation Tip

In the Think-Pair-Share, provide a graphic organizer for students to record trade-offs of pioneer species, such as nutrient cycling versus water retention.

What to look for

Facilitate a class discussion using the prompt: 'Imagine a large area of rainforest is cleared for cattle ranching. What types of species would you expect to see in the first year, after 10 years, and after 100 years? Explain the role of facilitation and inhibition in these changes.'

• Understand
• Apply
• Analyze
• Self-Awareness
• Relationship Skills

Activity 03

• Jigsaw
• 50 min · Small Groups

Jigsaw: Succession Case Studies

Assign small groups one of four case studies , Krakatoa recolonization, Yellowstone post-fire, Great Lakes sand dune succession, and Chesapeake Bay seagrass recovery. Each group reads their case, identifies succession type, key species, and rate of change, then teaches the class. Conclude with a structured comparison chart students complete individually.

Predict the long-term changes in species diversity during different stages of succession.

Facilitation Tip

For the Jigsaw, structure case-study groups so each member presents a distinct perspective before synthesizing the full sequence.

What to look for

Provide students with a list of species (e.g., lichen, moss, grass, shrub, young pine tree, mature oak tree). Ask them to arrange these species in the order they would likely appear during primary succession and then again during secondary succession, briefly justifying their arrangement for each.

• Understand
• Analyze
• Evaluate
• Relationship Skills
• Self-Management

Activity 04

• Experiential Learning
• 30 min · Individual

Data Analysis: Species Diversity Across Time

Provide students with species richness and evenness data from longitudinal field studies at multiple succession stages. Students graph the data, identify trends, and write a claim-evidence-reasoning paragraph predicting what happens to diversity at the climax stage. Debrief as a class to address contradictions between datasets.

Explain how primary succession differs from secondary succession in terms of time and species composition.

Facilitation Tip

When analyzing species diversity data, ask students to note trends in both species richness and evenness over time.

What to look for

Present students with two scenarios: one describing bare rock exposed by a retreating glacier, and another describing a forest after a wildfire. Ask them to write one sentence for each scenario identifying the type of succession and one sentence explaining why they chose that type.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

A few notes on teaching this unit

Teachers should emphasize the dynamic nature of succession by using longitudinal data rather than textbook diagrams. Avoid presenting succession as a linear, predictable endpoint; instead, highlight how disturbances like fire or human activity can reset or alter trajectories. Research suggests that students grasp succession more deeply when they analyze real datasets and discuss real-world case studies rather than relying on idealized models.

Students will confidently distinguish primary and secondary succession, identify pioneer species, and explain how disturbances shape ecosystem development. They will use evidence from activities to support their reasoning and connect concepts to real-world scenarios.

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Watch Out for These Misconceptions

• During the Gallery Walk, watch for students who assume all succession ends with a single, permanent climax community.

  Use the photo stations to guide students toward noticing evidence of disturbance, such as charred trees or human structures, and ask them to explain how these might restart succession.

• During the Jigsaw, listen for students who describe primary and secondary succession as simply faster or slower versions of the same process.

  Have groups compare their case studies side by side, focusing on the starting conditions (e.g., presence of soil) and how these differences impact pioneer species and timeline.

• During the Gallery Walk, students may assume pioneer species are always plants.

  Include photo stations with lichens, algae, or bacteria to prompt students to consider a broader range of pioneer organisms and their roles in nutrient cycling.

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Methods used in this brief

• Gallery Walk
• Think-Pair-Share
• Jigsaw
• Experiential Learning