Earth Processes and Landforms for Grade 4

Earth’s surface is always changing, even when those changes happen slowly. In Grade 4 science, students learn that rocks can break down, sediments can move, and landforms can be shaped over time by water, wind, ice, and living things.

Weathering Breaks Earth Materials Down

Weathering is the process that breaks rocks and other Earth materials into smaller pieces. This can happen when water freezes in cracks, when roots push into rock, or when wind and rain wear surfaces away over time.

Weathering does not have to move the material. It focuses on the breaking down of the material first.

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Example A rock may crack after water seeps in and freezes during cold weather.

Erosion Moves Sediment

Erosion happens when water, wind, ice, or gravity carries weathered material to a new place. The moved material is called sediment. Streams can carry sediment downstream, and wind can blow sand from one place to another.

Students should distinguish weathering from erosion by asking whether the material is only breaking apart or also moving.

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Example A river can carry bits of soil and rock away from a riverbank.

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Tip Ask, "Did it only break apart, or did it move too?" when comparing weathering and erosion.

Deposition Builds New Features

When moving sediment slows down and drops, the material settles in a new place. This is called deposition. Over time, deposition can help form sandbars, riverbanks, deltas, and other features.

This idea helps students see that Earth processes can wear places down and build places up.

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Example Sediment may settle where a river slows near its mouth.

Maps Show Patterns of Earth’s Features

Maps and models help scientists describe where mountains, valleys, rivers, plains, and coastlines are located. Students can look for patterns such as mountain chains, winding rivers, or flat plains.

Using map evidence strengthens the idea that landforms are not random. They follow patterns that can be studied and explained.

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Example A topographic map may show high mountains next to lower valleys.

📝 Key Vocabulary

Weathering

The breaking down of rock and other Earth materials into smaller pieces

Erosion

The movement of weathered material from one place to another

Sediment

Small pieces of rock, soil, or sand that can be carried and dropped

📐 Standards Alignment

4-ESS2-1 NGSS

Make observations and measurements to provide evidence of the effects of weathering or the rate of erosion by water, ice, wind, or vegetation.

4-ESS2-2 NGSS

Analyze and interpret data from maps to describe patterns of Earth’s features.

🔗 Glossary Connections

Weathering Weathering happens when rock slowly breaks apart into smaller pieces. Erosion Erosion happens when water, wind, ice, or gravity carries soil or rock away. Sediment Sediment is tiny bits of Earth material that water or wind can carry. Landform A landform is a natural shape of the land, like a hill, valley, or mountain.

⚠️ Common Mistakes to Watch For

Using weathering and erosion as if they mean the same thing
Forgetting that erosion involves movement
Thinking landforms never change because they often change slowly

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Real-World Connection Children can notice Earth processes at beaches, stream banks, hiking trails, construction sites, and schoolyards after strong rain or wind.

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Fun Fact! A canyon can form over a very long time as running water slowly wears away rock.