Section 1
Weathering Breaks Rocks into Smaller Pieces
Rocks break down through physical weathering (water, ice, plants) and chemical weathering (oxygen, acids). Over time, even enormous boulders can be reduced to pebbles or sand particles.
Grade 4 students learn how weathering, erosion, and deposition shape Earth's surface in this lesson from Chapter 3 of Science: A Closer Look. Students explore the difference between physical weathering and chemical weathering, discover how flowing water, wind, waves, and living things break rocks apart, and investigate how erosion transports weathered rock to new locations. A hands-on inquiry activity using soil, sand, and a spray bottle lets students model how rainfall moves land downhill.
Section 1
Weathering Breaks Rocks into Smaller Pieces
Rocks break down through physical weathering (water, ice, plants) and chemical weathering (oxygen, acids). Over time, even enormous boulders can be reduced to pebbles or sand particles.
Section 2
Water and Wind Transport Eroded Materials
Erosion occurs when weathered rock gets moved from one place to another. Rivers, waves, wind, and gravity all pick up and transport rock fragments, reshaping landscapes like the Grand Canyon.
Section 3
Glaciers Carve and Reshape Landscapes
Massive ice sheets called glaciers scrape across land, tearing rocks away and creating wider valleys. As glaciers melt, they deposit rocks and debris, forming moraines at their terminus.
Section 4
Humans Alter Landscapes More Rapidly
People change land through mining, building landfills, clearing forests, and construction. Unlike natural processes that work slowly, human activities can transform landscapes quickly, sometimes causing harm.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter
Expand to review the lesson summary and core properties.
Section 1
Weathering Breaks Rocks into Smaller Pieces
Rocks break down through physical weathering (water, ice, plants) and chemical weathering (oxygen, acids). Over time, even enormous boulders can be reduced to pebbles or sand particles.
Section 2
Water and Wind Transport Eroded Materials
Erosion occurs when weathered rock gets moved from one place to another. Rivers, waves, wind, and gravity all pick up and transport rock fragments, reshaping landscapes like the Grand Canyon.
Section 3
Glaciers Carve and Reshape Landscapes
Massive ice sheets called glaciers scrape across land, tearing rocks away and creating wider valleys. As glaciers melt, they deposit rocks and debris, forming moraines at their terminus.
Section 4
Humans Alter Landscapes More Rapidly
People change land through mining, building landfills, clearing forests, and construction. Unlike natural processes that work slowly, human activities can transform landscapes quickly, sometimes causing harm.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter