Weathering and Erosion: Shaping Landscapes

Active learning works for weathering and erosion because students can see processes that otherwise happen too slowly to observe. Physical demonstrations and simulations let learners connect abstract concepts to visible changes in materials, making the topic tangible and memorable.

• 6th Class
• Global Explorers: Our Changing World
• 4 activities
• 35 min–50 min

Learning Objectives

1. Compare and contrast the mechanisms of physical weathering (e.g., freeze-thaw, abrasion) and chemical weathering (e.g., carbonation, oxidation).
2. Explain how specific agents of erosion, such as water, wind, ice, and gravity, shape distinct landforms like valleys, canyons, and coastlines.
3. Analyze the impact of human activities, such as deforestation and quarrying, on accelerating rates of weathering and erosion.
4. Classify different types of rocks based on their susceptibility to physical and chemical weathering processes.

Gallery Walk

⏱ 50 min·Small Groups

Demonstration: Freeze-Thaw Weathering

Fill film canisters halfway with water, insert rocks, and place in freezer overnight. Next day, discuss lid pops from ice expansion. Compare to unglaciated controls and link to Irish granite tors. Groups sketch before-and-after changes.

Prepare & details

Compare and contrast the processes of physical and chemical weathering.

Facilitation Tip: During Demonstration: Freeze-Thaw Weathering, use a hair dryer to dry the rock fragments between cycles so students see temperature changes as the driving force.

Setup: Wall space or tables arranged around room perimeter

Materials: Large paper/poster boards, Markers, Sticky notes for feedback

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

Simulation Game

⏱ 35 min·Pairs

Simulation Game: River Erosion Races

In trays with sand and pebbles, pour water from heights to mimic rivers. Vary flow rates and observe sediment transport, channel cutting, deposition. Measure gully depths and discuss agents like velocity. Clean up collaboratively.

Prepare & details

Explain how different agents of erosion modify landforms over time.

Facilitation Tip: In Simulation: River Erosion Races, assign roles so each group member controls a variable (slope, flow rate, sediment load) to isolate its effect.

Setup: Flexible space for group stations

Materials: Role cards with goals/resources, Game currency or tokens, Round tracker

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

Stations Rotation

⏱ 45 min·Small Groups

Stations Rotation: Erosion Agents

Set stations for water (tray rivers), wind (hairdryers on sand), gravity (ramp rolls), ice (frozen soil blocks). Groups test, record landform changes every 5 minutes, rotate. Compile class chart of agent impacts.

Prepare & details

Assess the impact of human activities on rates of weathering and erosion.

Facilitation Tip: At Station Rotation: Erosion Agents, place a small fan near the wind station to show how wind can move fine particles even indoors.

Setup: Tables/desks arranged in 4-6 distinct stations around room

Materials: Station instruction cards, Different materials per station, Rotation timer

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

Concept Mapping

⏱ 40 min·Whole Class

Concept Mapping: Human Impacts Locally

Provide aerial maps of local area. Students identify erosion hotspots from construction or paths, predict changes, propose solutions like planting. Present findings to class with sketches.

Prepare & details

Compare and contrast the processes of physical and chemical weathering.

Facilitation Tip: During Mapping: Human Impacts Locally, provide highlighters in different colors for each erosion agent so students visually separate impacts.

Setup: Tables with large paper, or wall space

Materials: Concept cards or sticky notes, Large paper, Markers, Example concept map

• Understand
• Analyze
• Create
• Self-Awareness
• Self-Management

Teaching This Topic

Teachers should emphasize the sequence: weathering breaks rock, then erosion moves it. Avoid teaching these as single events. Research shows that hands-on models and repeated observations build stronger mental models than abstract explanations alone. Encourage students to document changes in journals to reinforce temporal understanding.

What to Expect

Successful learning looks like students correctly sequencing weathering before erosion and naming multiple agents of each process. They should also explain how human actions can speed up these natural processes and suggest ways to reduce their impact.

Watch Out for These Misconceptions

Common Misconception

During Demonstration: Freeze-Thaw Weathering, watch for students using 'weathering' to describe both breaking and moving rock.

What to Teach Instead

Pause the demonstration after the first freeze-thaw cycle and ask students to sort the rock fragments into two piles: those that stayed in place and those that have moved. Have them label each pile to clarify the distinction.

Common Misconception

During Station Rotation: Erosion Agents, watch for students assuming water is the only agent that causes erosion.

What to Teach Instead

At the wind station, provide a tray of flour and a straw. Have students blow through the straw to move the flour, then compare this to the water station’s results to highlight multiple agents.

Common Misconception

During Mapping: Human Impacts Locally, watch for students dismissing human activities as insignificant compared to natural processes.

What to Teach Instead

Use the schoolyard survey to show students how quickly paths erode underfoot. Have them measure ruts or cracks and calculate erosion rates over a school term to make human impacts visible and measurable.

Assessment Ideas

Quick Check

After Demonstration: Freeze-Thaw Weathering and Simulation: River Erosion Races, provide images of different landscapes and ask students to identify the primary erosion agent and one weathering process that likely contributed.

Exit Ticket

After Station Rotation: Erosion Agents, give students a scenario about a construction site near a river and ask them to write two sentences explaining how the construction could increase erosion and one suggestion to mitigate the impact.

Discussion Prompt

During Mapping: Human Impacts Locally, facilitate a class discussion using the prompt: 'Compare physical and chemical weathering for visitors to the Cliffs of Moher, including how each process affects the cliffs and why they are changing over time.'

Extensions & Scaffolding

• Challenge: Ask students to design an erosion-resistant garden using local materials and explain their choices in a short report.
• Scaffolding: Provide sentence starters for students to use when explaining their observations during the river erosion simulation.
• Deeper exploration: Invite students to research a famous landscape (e.g., Grand Canyon, Cliffs of Moher) and present how weathering and erosion shaped it over time.

Key Vocabulary

Physical Weathering	The breakdown of rocks into smaller pieces without changing their chemical composition. Examples include freeze-thaw action and abrasion.
Chemical Weathering	The process where rocks are altered or dissolved by chemical reactions, changing their composition. Examples include carbonation and oxidation.
Erosion	The process by which weathered material is transported from one place to another by natural agents like water, wind, ice, or gravity.
Agent of Erosion	A natural force that carries away weathered rock and soil, such as rivers, wind, glaciers, or gravity.
Landform	A natural feature of the Earth's surface, such as a mountain, valley, plain, or coastline, shaped by geological processes including weathering and erosion.