Erosion and Deposition

Active learning builds durable understanding of erosion and deposition because students observe how small, continuous processes accumulate over time to reshape landforms. Hands-on models and collaborative tasks make abstract energy gradients and particle-size sorting visible in minutes rather than years.

• 6th Grade
• Science
• 4 activities
• 20 min–50 min

Learning Objectives

1. Compare the depositional patterns of different agents of erosion (water, ice, wind, gravity) based on energy levels.
2. Analyze how specific landforms, such as deltas, moraines, and sand dunes, are created by deposition.
3. Explain the role of gravity as both an agent of erosion and a contributing factor to mass wasting.
4. Differentiate between the erosional and depositional features created by flowing water versus glacial ice.

Inquiry Circle

⏱ 50 min·Small Groups

Inquiry Circle: Stream Table Experiment

Groups use stream tables or plastic bins with sand and a water source to model erosion and deposition. They systematically vary slope angle and water flow rate, recording how each change affects the rate of erosion and the location where sediment is deposited. Groups present their findings as a cause-and-effect explanation.

Prepare & details

Explain how glaciers reshape landscapes over long periods.

Facilitation Tip: During the Stream Table Experiment, circulate with a stopwatch and call out elapsed time so students connect flow speed directly to erosion and deposition events.

Setup: Groups at tables with access to source materials

Materials: Source material collection, Inquiry cycle worksheet, Question generation protocol, Findings presentation template

• Analyze
• Evaluate
• Create
• Self-Management
• Self-Awareness

Think-Pair-Share

⏱ 20 min·Pairs

Think-Pair-Share: How Did That Canyon Form?

Show a cross-section diagram of the Grand Canyon layers alongside a present-day photograph. Partners discuss the agents of erosion and deposition involved, the time required to produce each layer, and what the area might have looked like before carving began.

Prepare & details

Analyze how the rate of erosion changes based on the type of soil or rock.

Facilitation Tip: For the Think-Pair-Share on canyon formation, provide labeled cross-sections so pairs trace the path of water and sediment step-by-step.

Setup: Standard classroom seating; students turn to a neighbor

Materials: Discussion prompt (projected or printed), Optional: recording sheet for pairs

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

Gallery Walk

⏱ 25 min·Small Groups

Gallery Walk: Erosion Agents

Post photographs of landforms produced by each major erosion agent: river, glacier, wind, ocean waves, and mass movement (landslide). Students identify the agent responsible, the resulting landform type, and one US location where this process is actively occurring.

Prepare & details

Differentiate between erosion and deposition and their resulting landforms.

Facilitation Tip: During the Gallery Walk, place a small mirror at each station so students view landform shapes from multiple angles before recording observations.

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

Experiential Learning

⏱ 30 min·Small Groups

Sorting Activity: Grain Size and Deposition Order

Groups receive mixed samples of gravel, sand, silt, and clay. They predict and then test the deposition order by adding the mixed sample to a water column in a clear tube and timing when each size class settles. Groups connect their results to real-world river delta and floodplain formation.

Prepare & details

Explain how glaciers reshape landscapes over long periods.

Facilitation Tip: In the Sorting Activity, have students physically stack sediment cards from largest to smallest to reinforce deposition order rules.

Setup: Varies; may include outdoor space, lab, or community setting

Materials: Experience setup materials, Reflection journal with prompts, Observation worksheet, Connection-to-content framework

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

Teaching This Topic

Start with the stream table to anchor the concept in observable time scales, then contrast river and glacial erosion using the gallery walk to highlight valley shapes and grain textures. Avoid over-reliance on diagrams alone; the physical model makes energy gradients concrete. Research shows students grasp deposition order best when they sort real sediment samples before abstracting the pattern.

What to Expect

Successful learning looks like students explaining how energy loss causes deposition in specific layers, predicting the sequence of sediment settling, and distinguishing between agents by observing landform shapes and grain sizes.

Watch Out for These Misconceptions

Common Misconception

During the Stream Table Experiment, watch for students assuming erosion only happens during sudden, large changes in water volume.

What to Teach Instead

Pause the flow every 30 seconds and point out tiny ripples and particle movements; ask students to estimate how much material moves in one minute and multiply by the total run time to reveal continuous change.

Common Misconception

During the Gallery Walk, listen for students describing glaciers and rivers as using the same erosion method.

What to Teach Instead

Place a U-shaped valley image next to a V-shaped valley image and ask students to trace the pattern of scraping versus downcutting using their fingers on the printed shapes.

Common Misconception

During the Sorting Activity, watch for students believing deposition requires agents to stop completely.

What to Teach Instead

Have students sort sediment cards while holding them at different heights above the table: higher drops simulate losing energy early, lower drops represent energy loss later, showing deposition begins with reduced speed, not full stop.

Assessment Ideas

Exit Ticket

After the Gallery Walk, distribute images of a delta, sand dune, and U-shaped valley and ask students to label the primary agent for each and write one sentence explaining how energy loss shaped the landform.

Quick Check

During the Stream Table Experiment, pause the flow when the water first enters the lake tray and ask students to list the sediment types deposited in order, explaining why the largest particles settle first.

Discussion Prompt

After the Think-Pair-Share on canyon formation, pose the prompt: ‘Gravity pulls a landslide downhill; what happens to the material afterward?’ and ask pairs to connect mass wasting to deposition in valleys or fans.

Extensions & Scaffolding

• Challenge: Ask students to design a flood-control measure using the stream table and predict how it changes erosion patterns downstream.
• Scaffolding: Provide pre-labeled sediment cards with size ranges already matched to deposition order for students who need support.
• Deeper exploration: Have students calculate the velocity drop needed to deposit sand versus clay using the stream table’s slope and flow-rate data.

Key Vocabulary

Sediment Load	The material (rocks, sand, silt, clay) that is being transported by water, wind, ice, or gravity.
Deposition	The geological process in which sediments, soil, and rocks are added to a landform or landmass, often by a slowing agent of erosion.
Mass Wasting	The downslope movement of rock, regolith, and soil under the direct influence of gravity, such as landslides and rockfalls.
Glacial Till	Unsorted, unstratified sediment deposited by glacial ice, often containing a mixture of clay, sand, gravel, and boulders.
Alluvium	Sediments deposited by flowing water, typically found in riverbeds, floodplains, and deltas.