---
title: "Types of Rock"
description: "Know the three main rock types: igneous forms from cooling melted rock, many sedimentary rocks form from pieces pressed and stuck together, and metamorphic rock changes through heat and pressure witho"
canonical: https://lightmysky.com/learn/science/types-of-rock-mt_NYA50DFcOO
source: https://lightmysky.com/learn/science/types-of-rock-mt_NYA50DFcOO.md
retrieved: 2026-10-19
---

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# Types of Rock

Know the three main rock types: igneous forms from cooling melted rock, many sedimentary rocks form from pieces pressed and stuck together, and metamorphic rock changes through heat and pressure without melting; fossils are usually found in sedimentary rock

Subject: Science · Area: Volcanoes & Earthquakes · Ages 7 to 9
Page: https://lightmysky.com/learn/science/types-of-rock-mt_NYA50DFcOO

## Ready when they can

- Name the three main rock types: igneous, sedimentary, metamorphic
- Explain that igneous rock forms when lava or magma cools and hardens
- Explain that fossils are usually found in sedimentary rock because sediment can bury and preserve remains or marks of past living things

## Lesson: The Three Types of Rock

Rocks form in different ways. Scientists group them into three main types: igneous, sedimentary, and metamorphic. Learning how a rock formed helps you decide which group it belongs to.

**Example.** Ben sees lava flowing in a volcano video. When it cools and hardens, it becomes igneous rock. Melted rock underground is called magma. At the surface, it is called lava. Cooling magma also forms igneous rock, even if it never reaches the surface.

*(drawing: Many sedimentary rocks form when small pieces settle, then get pressed and stuck together.)*

Sand, mud and small rock pieces are called sediment. Many sedimentary rocks form as sediment settles in layers. Over time, the pieces get pressed and stuck together. Sediment can bury remains or marks of past living things, such as shells or footprints. These can become fossils. Fossils are usually found in sedimentary rock, but many sedimentary rocks have none.

Metamorphic rock forms when heat and pressure change an existing rock without melting it. Pressure means pushing or squeezing. Some metamorphic rocks have bands. Bands alone do not prove a rock's type. If rock melts and later cools, it forms igneous rock instead.

**Recap.** Igneous rock forms from cooling melted rock. Many sedimentary rocks form from joined pieces and can hold fossils. Metamorphic rock changes through heat and pressure without melting.

## Practice

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

## Needs first

- [Earth's Layers](https://lightmysky.com/learn/science/earths-layers-mt_jwElFY7Syd)
- [Properties of rocks](https://lightmysky.com/learn/science/properties-of-rocks-mt_R6YoRXkRxS)
- [What Is a Volcano](https://lightmysky.com/learn/science/what-is-a-volcano-mt_S9SKah-yi_)
- [Earth's Rocky Ground](https://lightmysky.com/learn/science/earths-rocky-ground-mt_uUa6cgv8zV)

## Opens up

- [Rock Layers & Relative Dating](https://lightmysky.com/learn/science/rock-layers-and-relative-dating-mt_EGIlsfHxb6)
- [How Rocks Change Over Time](https://lightmysky.com/learn/science/how-rocks-change-over-time-mt_z7AJZapsJj)