---
title: "Erosion and weathering"
description: "Make observations and measurements to provide evidence of the effects of weathering or the rate of erosion by water, ice, wind, or vegetation"
canonical: https://lightmysky.com/learn/science/erosion-and-weathering-mt_vAP_A986IQ
source: https://lightmysky.com/learn/science/erosion-and-weathering-mt_vAP_A986IQ.md
retrieved: 2026-10-19
---

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# Erosion and weathering

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

Subject: Science · Area: Earth's Systems · Ages 9 to 10
Page: https://lightmysky.com/learn/science/erosion-and-weathering-mt_vAP_A986IQ

## Ready when they can

- Define weathering (breaking down of rock in place) and erosion (movement of broken rock/soil)
- Describe the effects of at least three agents of weathering/erosion: water, ice, wind, vegetation
- Provide evidence from observations showing how weathering or erosion has changed a landscape

## Lesson: How Weathering and Erosion Change the Land

Weathering is when rock or soil breaks apart right where it sits. Erosion is when those broken pieces get carried away to a new place. Weathering starts the job. Erosion moves the pieces.

*(drawing: A rock changes step by step as weathering breaks it apart, but it hasn't moved yet.)*

**Example.** At a river bank, moving water rubs against the soil every day. Over many years, the water carries away so much soil that the bank slowly moves back. That change in the land is evidence of erosion.

Water is not the only agent. Ice cracks rock apart when it freezes inside a crack and expands. Wind blasts tiny grains of sand against rock and wears it smooth. Plant roots grow into cracks and pry the rock apart.

**Tip.** To find evidence of weathering or erosion, look for rounded edges, piles of loose rock, or a landscape that looks different in old photos compared to now.

**Recap.** Weathering breaks rock down in place, and moving water, ice, wind, or plant roots erode the pieces away, slowly changing the land.

## Practice

8 questions on this page, each with its working shown.

## Needs first

- [Types of rocks](https://lightmysky.com/learn/science/types-of-rocks-mt_bqL8DD1SbV)
- [Properties of rocks](https://lightmysky.com/learn/science/properties-of-rocks-mt_R6YoRXkRxS)

## Opens up

- [Finding patterns in data](https://lightmysky.com/learn/science/finding-patterns-in-data-mt_-G6erQvLig)
- [What the Ice Left Behind](https://lightmysky.com/learn/geography/what-the-ice-left-behind-mt_D-aB1k0K73)
- [Coasts on the Move](https://lightmysky.com/learn/geography/coasts-on-the-move-mt_IVnXDRpfqE)
- [Preventing Erosion](https://lightmysky.com/learn/science/preventing-erosion-mt_m6UaSmrQVG)
- [Weathering, Erosion and How Soil Forms](https://lightmysky.com/learn/science/weathering-erosion-and-how-soil-forms-mt_nQOPOt1VTH)
- [How a River Shapes Its Valley](https://lightmysky.com/learn/geography/how-a-river-shapes-its-valley-mt_v6D9mgcf0P)
- [How Rocks Change Over Time](https://lightmysky.com/learn/science/how-rocks-change-over-time-mt_z7AJZapsJj)