Rocks

Science Companion Field TripsA “Science in Real Life” Series

Science Field Trip

A Virtual “Rock Walk” through Indiana

“Where do Rocks Come from?”Selections from the digital

Teacher Lesson Manual

Come on a virtual field trip matching module sample lessons with special places or current events!

www.sciencecompanion.com

Join us on a wander to find out where some of the cool rocks in Indiana came from.

Indiana has glaciated rock and some of the best sedimentary deposits in the US

and the world for the time periods represented...

Ordovician Silurian

Devonian Carboniferous

But not very muchigneous or metamorphic rock,

except for a few rocks that took a ride...do you know how?

Indiana

The Falls of the Ohio State Park is a great place to find sedimentaryrock.

This is a nautoloid.

It was an ancestor of the nautilus.

http://igs.indiana.edu/geology/fossils/nautiloids/index.cfm

Devonian formations at The

Falls of the Ohio.

This rock started as the bottom of shallow

inland seas.

Rock from the Ordovician period often has fossils of

nautoloids.

Turn the page to find out how you can learn more about where rocks come from!

A glacier.

Glaciers are messy!They also leave stuff behind when they melt.

Other rocks were shaped by the glaciers that covered the Northern half of Indiana about

16,000 years ago.

http://www.nature.org/wherewework/northamerica/states/indiana/misc/art23385.html

These limestone formations are called glacial striations.

Like granite, that people use for kitchen counters. Or stone walls

or boulders that you might have in your yard. Lots of people use these boulders this way in Indiana!

Our thanks to Tina Harris for being our idea source about Indiana rocks! She is a teacher at Anderson Community Schools Corporation, a HASTI Board Member, and a rock hound.

In Indiana, they left behind igneous and metamorphic rocks that rode the glaciers down from the north.

Teacher Lesson Manual

Rocks

| Rocks | TABLE oF coNTENTs �

suggested Full-Year schedule . . . . . . . . . Inside Front Cover

Welcome to science companionPhilosophy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Finding What You Need in Science Companion . . . . . . . . . . . . . . . . . 8

Cross-Curricular Integration and Flexible Scheduling . . . . . . . . . . . 10

Differentiating Instruction for Diverse Learners . . . . . . . . . . . . . . . . 12

Unit overviewIntroduction to the Rocks Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Unit Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Lessons at a Glance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Preparing for the UnitThe Rocks Science Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Science Library and Web Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Before You Begin Teaching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Teacher Directions: Labeling the Rock and Mineral Collection and the Fossil Collection . . . . . . . . . . . . . . . . . . . . . . . . 46

Lessons1 What Is a Rock?* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

2 Properties of Rocks* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

3 Where Do Rocks Come From?* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

4 Rocks Are Made of Minerals* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

5 Properties of Minerals* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

6 More Properties of Minerals* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

7 Minerals as Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

8 Introduction to Fossils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

9 Mold and Cast Fossils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 Teacher Directions: Making Rock Dough and Rock Goo for Model Mold and Cast Fossils . . . . . . . . . . . . . . . . . . . . . . . . . . 154

10 Petrified Fossils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158 Teacher Directions: Making an Epsom Salt Solution for Petrified Fossil Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168

11 A Rock of My Own* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170

* Indicates a core lesson

Table of contents

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skill Building Activities1 Using Magnifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182

2 Observing and Describing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190

3 Using Field Guides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200

Teacher Background Information . . . . . . . . . . . . . . . . . . 208

standards and BenchmarksStandards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226

Benchmarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228

Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232

Teacher Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236

| Rocks | PHILosoPHY �

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Almost anyone who has spent time with children is struck by the tremendous energy they expend exploring their world. They ask “why” and “how.” They want to see and touch. They use their minds and senses to explore the things they encounter and wonder about. In other words, children are already equipped with the basic qualities that make a good scientist.

The goal of the Science Companion curriculum is to respond to and nourish children’s scientific dispositions by actively engaging their interests and enhancing their powers of inquiry, observation, and reflection. Learning by doing is central to this program.

Each Science Companion lesson incorporates interesting and relevant scientific content, as well as science values, attitudes, and skills that children in the elementary grades should begin to develop. These “habits of mind,” along with science content knowledge, are crucial for building science literacy and they are an integral part of the Science Companion program. Be aware of them and reinforce them as you work with children. With experience, children will develop the ways they demonstrate and use the following scientific habits of mind.

Habits of MindWondering and thinking about the natural and physical worldChildren’s curiosity is valued, respected, and nurtured. Their questions and theories about the world around them are important in setting direction and pace for the curriculum. Children are encouraged to revise and refine their questions and ideas as they gain additional information through a variety of sources and experiences.

Seeking answers through exploration and investigationChildren actively seek information and answers to their questions by trying things out and making observations. Children continually revise their understanding based on their experiences. Through these investigations, they learn firsthand about the “scientific method.” They also see that taking risks and making mistakes are an important part of science and of learning in general.

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Pursuing ideas in depthChildren have the opportunity to pursue ideas and topics fully, revisiting them and making connections to other subjects and other areas in their lives.

Observing carefullyChildren are encouraged to attend to details. They are taught to observe with multiple senses and from a variety of perspectives. They use tools, such as magnifying lenses, balance scales, rulers, and clocks, to enhance their observations. Children use their developing mathematics and literacy skills to describe, communicate, and record their observations in age-appropriate ways.

Communicating clearlyChildren are asked to describe their observations and articulate their thinking and ideas using a variety of communication tools, including speaking, writing, and drawing. They learn that record keeping is a valuable form of communication for oneself and others. Children experience that working carefully improves one’s ability to use one’s work as a tool for communication.

Collaborating and sharingChildren come to know that their ideas, questions, observations, and work have value. At the same time, they learn that listening is vitally important, and that exchanging ideas with one another builds knowledge and enhances understanding. Children discover that they can gain more knowledge as a group than as individuals, and that detailed observations and good ideas emerge from collaboration.

Developing critical response skillsChildren ask, “How do you know?” when appropriate, and are encouraged to attempt to answer when this question is asked of them. This habit helps develop the critical response skills needed by every scientist.

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R o c k sc L U s T E R �DESCRIBING ROCKS

3Lesson

Big Idea

The earth forms and changes rocks. Some of a rock’s properties are a result of how it was formed.

key Notes

• Consider reading and discussing The Magic School Bus Inside the Earth to the class during language arts time to allow more time for the exploration and follow-up discussion. If you can locate additional copies of the book, you might rather conduct the read-aloud and discussion in small groups as part of your reading instruction.

• See the Preparation section for details about setting up rock stations in the classroom for this lesson. You may want to enlist help with these preparations.

• For more information about the science content of this lesson, see the “Rock Formation and the Rock Cycle” section of the Teacher Background Information.

overview

Children are introduced to the three main groups of rocks—igneous, sedimentary, and metamorphic—and learn about the earth processes that formed them. They visit three stations—one devoted to each major rock group—and look for rocks that display typical characteristics of that type of rock.

Where Do Rocks come From?

A QUIck Look

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3Lessonstandards and Benchmarks

This lesson supports The Physical Setting Benchmark 4C and Earth and Space Science Standard D (Changes in Earth and Sky) through a discussion of the processes that form and change rocks on Earth. The discussion reinforces the concept that “Change is something that happens to many things.” It also supports Physical Science Standard B (Properties of Objects and Materials) as children focus on specific properties that “can be used to separate or sort” rocks by type.

Lesson Goals

1. Become aware of the three major groups of rocks on Earth and the processes that formed them.

2. Discover that how a rock was formed affects some of its properties.

Assessment

Review your notes from the note recording tool to assess the children’s observational skills, as well as their awareness of how a rock’s formation affects its properties. You can note this information on Assessment 1 and Assessment 3.

Teacher Masters 2, 4, and 6; Assessments 1 and 3 and Note Recording Tool

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Materials

Item Quantity Notes

ExploraGearBasalt 2 pieces For igneous rock sets.

Conglomerate 2 pieces For sedimentary rock sets.

Gneiss 2 pieces For metamorphic rock sets.

Granite 2 pieces For igneous rock sets.

Limestone 2 pieces For sedimentary rock sets.

Magnifying lenses Several per station For closely examining rocks.

Marble 2 pieces For metamorphic rock sets.

Metaconglomerate (metamorphosed conglomerate)

2 pieces For metamorphic rock sets.

Obsidian (pitchstone) 2 pieces For igneous rock sets.

Porphyry 2 pieces For igneous rock sets.

Pumice 2 pieces For igneous rock sets.

Rhyolite 2 pieces For igneous rock sets.

Sandstone 2 pieces For sedimentary rock sets.

Scoria 2 pieces For igneous rock sets.

Shale 2 pieces For sedimentary rock sets.

Slate 2 pieces For metamorphic rock sets.

Tree cross section 1 For sorting.

Classroom SuppliesTape 1 roll To tape labels and rock charts to stations

From Previous Lessons“K-W-L” chart From Lesson 1.

Curriculum ItemsBook: The Magic School Bus Inside the Earth*

Rocks Science Notebook, pages 6-8

Teacher Master “Igneous Rocks”

Teacher Master “Metamorphic Rocks”

Teacher Masters “Rock Clues”

Teacher Masters “Rock Labels”

Teacher Master “Sedimentary Rocks”

Teacher Master “Note Recording Tool” (optional)

Rubric 1: Properties of Rocks and Minerals (optional)

Checklist: Observing and Describing (optional)

* If this book is not available, you will receive a substitute that is appropriate for this lesson.

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Preparation

Teacher NoTe: Complete the following steps to set up three “rock type” stations—igneous, sedimentary, and metamorphic—each with two sets of identical materials.

Make two copies of each page of the Teacher Masters “Rock Clues.”

Create two sets of rock labels for each station by making two copies of each page of the Teacher Masters “Rock Labels” and cutting out the labels.

Distribute the following materials to three different stations, each clearly labeled with a name (igneous, sedimentary, or metamorphic). Divide the materials into two separate, but identical sets, so that two groups of children can work at each station at the same time.

• Igneous station—Two samples each of basalt, granite, obsidian, porphyry, pumice, rhyolite, and scoria placed on their corresponding labels; two copies of the Teacher Master “Rock Clues: Igneous Rocks”; several magnifying lenses

• Sedimentary station—Two samples each of conglomerate, limestone, sandstone, and shale placed on their corresponding labels; two copies of the Teacher Master “Rock Clues: Sedimentary Rocks”; several magnifying lenses

• Metamorphic station—Two samples each of gneiss, marble, metaconglomerate, and slate placed on their corresponding labels; two copies of the Teacher Master “Rock Clues: Metamorphic Rocks”; several magnifying lenses

Secure the rock labels and the rock clues sheets to the stations with tape.

Vocabularyigneous rocks . . . . . . . . Rocks that form when melted rock

(magma) cools and hardens above ground or underground.

lava . . . . . . . . . . . . . . . . . . Melted rock that flows onto the earth.

magma . . . . . . . . . . . . . . . Melted rock found inside the earth.

metamorphic rocks . . Rocks that form when other rocks are heated and squeezed together inside the earth.

sediment . . . . . . . . . . . . . Tiny pieces of rocks, shells, sand, and clay that pile up on the bottoms of lakes and oceans.

sedimentary rocks . . . Rocks that form when layers of sediment are pressed and cemented together over time.

Teacher Masters 14-16

Teacher Masters 17-19

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Teaching the Lesson

Engage

Introductory Discussion1. Gather the children around and read aloud The Magic School

Bus Inside the Earth.

Teacher NoTe: “The Magic School Bus” series can be difficult to share with large groups. It is not necessary to read every conversation bubble. Focus instead on the main text as well as the student reports that appear in the margins. Stop periodically during the reading to review and discuss sections that focus on how rocks are formed and changed by the earth over time.

As an alternative, substitute the video version for the book and pause the video at appropriate points to emphasize the three main rock types and the earth processes that formed them.

2. After the reading, discuss the book and review some of the ways rocks are formed and changed over time.

3. Have the children turn to pages 6-8 in their science notebooks. Point out that each page contains information about one of the three main types of rocks. Go over the first paragraph on each page, which offers a brief description of how each rock type is formed.

Use the note recording tool during the introductory discussion and then again in the synthesizing discussion to record comments that demonstrate an awareness of how the earth forms and changes rocks, and how a rock’s formation can affect its properties.

Science Notebook pages 6-8

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Explore

Examining Igneous, Sedimentary, and Metamorphic Rocks1. Point out the three stations to the children, one corresponding

to each main rock type.

2. Divide the class into three groups and assign each group to a station. Within each station, direct half of the group to work with one set of materials and the other half to work with the other set. Let the children know that the sets are identical.

3. Show the children the “Igneous Rocks,” “Sedimentary Rocks,” and “Metamorphic Rocks” clue sheets at each station. Explain that each box on the sheets contains a description that matches some rocks of that type.

4. Model the steps children should follow to examine each set of rocks:

a. Read the description in the first box on the sheet.

b. Find all the rocks that match the description and place them on the page inside the box.

c. Do the same for all the boxes on a sheet, then return the rocks to the proper place, using their labels. (You probably will only need to demonstrate the procedure for one or two boxes.)

5. Have the children rotate through each station so they can examine the samples from all three rock groups.

Circulate around the room as the groups discuss and sort rocks to assess how well the children are able to note significant rock details; also listen for comments about rock formation.

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Reflect and Discuss

Synthesizing

Teacher NoTe: During this discussion, have available a set of rocks of each type from the stations.

1. Go over page 6 about igneous rocks in the science notebook.

• Review the explanation of how igneous rocks were formed.

• Read the clues for igneous rocks, emphasizing the text in bold. Remind children that they looked for these characteristics during the exploration.

• Let the children help you select and display a rock that matches each igneous rock clue.

• Discuss children’s ideas about why a rock that was formed this way might have these characteristics.

2. Repeat this procedure for sedimentary and metamorphic rocks, using pages 7-8 of the science notebook.

3. (Optional) Show the children the three sets of rocks grouped by rock type and talk with them about the groupings.

• Point out the variety found in a single group.

• Encourage them to offer explanations for why there would be such a wide variety.

• Guide the children to the realization that what the rocks in each group have in common is how they were formed.

4. Now or shortly after the lesson, make connections to the previous lessons by doing the following:

• Add new questions and understandings to the “K-W-L” chart from Lesson 1. If no one mentions the Big Idea for this lesson, review these concepts and add the information to the L (Learned) column.

• Revisit the” undecided” pile in the Science Center and move objects that weren’t formed by the earth into the non-rock pile.

language arts connectionSee the Language Arts Extensions for information about additional books that you might want to read aloud to reinforce or extend the concepts presented in this lesson.

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ongoing Learning

science centerPost copies of the three pages—one for each rock type—of the Teacher Masters “Rock Clues” in the Science Center. Put a container to hold rocks near each page. Challenge the children to use the clues to sort the class rock collection into the containers. The children should be familiar with the clues since they worked with them in their science notebooks.

Extending the Lesson

Further science ExplorationContact a state geological survey office to inquire about “road cuts” in your area. Plan a field trip to one of the recommended sites. Bring a geologist along or a copy of the geological survey to identify the interesting features of the road cut.

Language Arts ExtensionsRead How to Dig a Hole to the Other Side of the World, by Faith McNulty, to the class. This book, in which a young boy provides instructions for digging the deepest hole in the world, will add to the children’s understanding of the earth beneath their feet.

For children who want to learn even more, consider the books, The Pebble in My Pocket, by Meredith Hooper, Earthsteps: A Rock’s Journey through Time, by Diane Nelson Spickert, and The Big Rock, by Bruce Hiscock, as in-depth and challenging reading selections. These books will add to the children’s understanding of rock formation by following a single rock’s changes over a very long period of time.

Mathematics ExtensionHelp the children create a bar graph displaying how high the temperature climbs at each of the earth’s layers. (Refer the children to The Magic School Bus Inside the Earth, pages 28-29, for the data and an illustration.) Label the graph so that the earth’s layers appear in consecutive order, beginning with the crust.

• Crust–900° C

• Mantle–3000° C

• Outer Core–4000° C

• Inner Core–6500° C

Materials: Class rock collection, containers, Teacher Masters “Rock Clues”

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Teacher Background InformationIntroduction

The Rocks Unit introduces children to geology, the scientific study of Earth’s origin, history, and structure. During the early-elementary grades, children have difficulty conceptualizing the long-term processes that shape and change the earth. Therefore, this unit focuses on children’s more immediate experiences with rocks, minerals, and fossils, and lays groundwork for later learning about earth processes.

Rocks are very familiar to most children, although not many children have stopped to consider what rocks are made of, how they are formed, why they look different from one another, or even how you know something is a rock. The Rocks Unit invites children to explore and learn about these and many other topics, and helps children realize the many opportunities for scientific investigation that exist right in their own backyards (or alleys or driveways!). In addition, the Rocks Unit provides an interesting and meaningful context for practicing important scientific process skills, such as observation, description, and classification.

Rocks and MineralsRocks are solid substances formed by the earth. They are usually a mixture of many minerals, although it is possible for rock—for example limestone or marble—to contain only one type of mineral. Rocks are non-living but sometimes contain materials from once-living organisms. The mineral composition, chemical and physical properties, and ages of rocks vary widely.

Minerals are naturally occurring, inorganic, crystalline substances. Every mineral consists of a single solid with a definite chemical composition. Minerals are the building blocks of rocks; all rocks are made of minerals.

Children frequently confuse the words “rock” and “mineral,” or use them interchangeably. In the Rocks Unit children study rocks, then study minerals. This sequence helps children understand that the varied substances they observe within rocks are different, specific minerals.

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Rocks Lessons 1, 2, and 3 focus on getting children to consider rocks—what they are, how to describe and classify them, and how they are formed. Rocks Lesson 4 has the children examine, touch, and identify mineral samples both as discrete minerals and as constituents of granite pegmatite rock, thereby reinforcing their understanding that rocks are made of minerals. By Lessons 5 and 6, the children are investigating the properties of minerals, including color, streak, and hardness.

Rock Formation and the Rock cycleOne way geologists cope with the tremendous variety of materials on Earth is to classify them according to origin. There are three main types of rocks: igneous, sedimentary, and metamorphic. These types of rocks are distinguished from one another by how they are formed and shaped by the earth.

Igneous RocksIgneous rocks are formed by the cooling and solidification of hot, molten magma, or melted rock. (Igneous rocks get their name from the Latin word ignis, which means fire.) Cooling causes crystallization, and the rate at which the molten rock cools makes a great difference in the kinds of crystals that form. The nature and the properties of the rocks vary greatly, depending partly on the composition of the original magma and on the conditions under which the magma solidified.

Rocks that cool within the earth from magma, such as granite, are called intrusive. As a result of cooling slowly, intrusive rocks tend to have large, visible crystals and be coarse-grained. These types of rocks are often called plutonic igneous rocks. Rocks that have cooled the slowest and have the largest, coarsest grains are called pegmatites.

Rocks that cool on the earth’s surface, such as basalt and rhyolite, are called extrusive. Magma can get to the earth’s surface as the result of a volcanic eruption or by flowing out through cracks in the earth. Extrusive rocks cool very rapidly and therefore tend to have small crystals and be fine-grained. They are often called volcanic igneous rocks. Some may be glassy (such as obsidian), porous (such as pumice) from gases that were trapped inside the lava as it cooled, or both (such as scoria).

Some rocks, called porphyries, have both very large crystals and very small ones. These rocks formed with a change in the rate of cooling. For example, magma may have started cooling slowly deep beneath the earth’s surface, producing some large crystals, but then been extruded as lava, increasing the rate of cooling to produce extremely small crystals between the large ones.

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Examples of igneous rocks in the ExploraGear include granite, basalt, rhyolite, obsidian, scoria, porphyry, pumice, and pegmatite.

Sedimentary Rocks Erosion refers to a variety of processes by which soil or rock material is loosened, dissolved, or otherwise worn away from any part of the earth’s surface. All types of rocks are exposed to weathering agents, such as wind, water, and temperature changes, that slowly break them down into rock particles—some very small, such as sand or silt; others larger, such as pebbles. These rock particles are referred to as sediments.

Sedimentary rocks are the most abundant rocks on the surface of the earth, covering about three-quarters of its surface. Sedimentary rocks form when sediments, such as sand, clay, soil, rock particles, and skeletons of microscopic animals, are carried away by water and eventually settle in layers on the bottom of lakes, ponds, and oceans. As the layers build up, the weight of the upper, newer layers and any water that might be on top of them press the sediments in the lower layers together very tightly. In time, these sediments can become rock by being compacted by pressure from the weight above or cemented together by mineral precipitation from water. Often both cementation and compaction happen together.

Geologists classify sedimentary rocks as clastic, organic, or chemical rocks. Clastic rocks are sedimentary rocks made from the fragments of previously existing rocks that were broken down and cemented together over time to form new rock. Examples of clastic rocks are conglomerate, sandstone, and shale. Organic rocks are formed either directly or indirectly from material that was once living. For example, limestone deposits may be formed from the calcium carbonate shells of creatures such as clams and certain microorganisms, or from reef-building coral. Coal, which is made of the decayed remains of swamp plants that were compressed into rock over long periods of time, is another example of an organic rock. Chemical rocks are sedimentary rocks formed when a sea or a lake dried up, leaving behind large amounts of minerals that were dissolved in the water. As the water evaporated, the remaining minerals formed rocks such as gypsum and rock salt (both made from a single mineral). Some limestone is also chemical rock.

Examples of sedimentary rocks in the ExploraGear include sandstone, limestone, shale, and conglomerate.

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Metamorphic RocksMetamorphic rocks are formed by the physical or chemical (or both) change of rocks through intense heat and pressure under the surface of the earth. (The root word morph means form, and the prefix meta means change.) All kinds of rocks can be metamorphosed—sedimentary, igneous, and other metamorphic rocks. For example, marble, a metamorphic rock, is formed as a result of thermal (heat and pressure) changes to limestone, a sedimentary rock. (If the heat and pressure were intense enough to melt the rocks, they would re-form as igneous rocks.)

Metamorphic rocks tend to be either foliated or unfoliated. Foliated metamorphic rocks have mineral crystals arranged in parallel layers or bands and often break into layers along these bands. Examples include schist, slate, and gneiss. Unfoliated metamorphic rocks are not banded and do not break into layers. Examples include marble and quartzite.

Examples of metamorphic rocks in the ExploraGear include marble, slate, gneiss, and metaconglomerate.

The Rock Cycle: “Recycling” RocksThe series of changes that transform one type of rock into another make up the rock cycle. As the following diagram illustrates, rocks are continually being recycled and re-formed by earth processes.

IgneousRock

MetamorphicRock

SedimentaryRock

magma

Sediments

cooling

melting

melting

heat and pressu

re

weathering and erosion

weathering and erosion

weatheringand erosion

compactionand cementation

heat and pressure

| Rocks | TEAcHER BAckGRoUND INFoRMATIoN 2�2

Weathering and erosion occur on Earth’s surface, and act on all exposed rocks. The sediments that are the source of sedimentary rocks can be weathered and eroded from igneous, sedimentary, or metamorphic rocks. Any of these three types of rocks will undergo changes and create a metamorphic rock if subjected to heat and pressure. If the heat and pressure are intense enough and the rock melts, it forms an igneous rock when it cools. Many cycles in nature, like the changing of the seasons or the phases of the moon, occur in a definite order, but the rock cycle has no definite sequence.

Because the Rocks Unit is written for early-elementary children, it introduces, but does not focus on, rock formation or the rock cycle. The primary goal is to introduce the three main types of rocks and how they are formed, without going into detail about earth processes. Children also learn that a rock’s properties result, in part, from how it was formed. Many children view rocks and minerals as being permanent and primitive; they often have difficulty with the idea that rocks and minerals are constantly being formed and changed. The lessons in the Rocks Unit aim to help children become familiar with the idea of changes in the earth’s materials through processes such as erosion and weathering, crystallization, and fossilization. Through this introduction, the Rocks Unit lays a foundation for future understanding of long-term geologic processes and the rock cycle.

Rock Properties and IdentificationUnlike minerals, rocks cannot be identified with a simple series of tests. To confirm the identity of a rock, geologists in the field take samples back to the laboratory and examine thin slices of the rock under a microscope to determine its name and classification. They use various indicators to try to determine what type of rock it is, and they consider the rock’s texture, color, and composition. You might want to go to www.sciencecompanion.com/links to find links to web sites with additional information about identifying rocks.

Rock TypeThe first step in identifying a rock is to determine whether it is an igneous, metamorphic, or sedimentary rock. This can be difficult, but there are many useful indicators. For example, igneous rocks often have interlocking crystals of similar size and a random orientation of their mineral grains. Sedimentary rocks often show the horizontal layering that resulted from how they were deposited and are often softer, or more crumbly, than the other types. Metamorphic rocks have interlocking crystals that are not always the same size. Often, the crystals in metamorphic

2�3Rocks | TEAcHER BAckGRoUND INFoRMATIoN |

rocks are parallel to one another and point in a single direction, resulting in a banded appearance (foliation). This layering, or banding, is a reaction to being formed under pressure, which makes it different from the layering in sedimentary rocks.

TextureTexture is a primary identifying characteristic, or property, of rocks. Texture refers to the surface characteristics and appearance of the rock, including the size and shape of its mineral crystals. In general, rocks with large mineral crystals are described as coarse-grained, while those with very small or invisible crystals are called fine-grained.

The texture of a rock is linked to the way it was formed. Depending on the type of rock, different aspects of texture reveal different kinds of information. For example, the size of the grains in igneous rocks indicates the rock’s rate of cooling and, therefore, where the rock formed (cooling quickly on the surface or slowly underground). The texture of clastic sedimentary rocks indicates the size of the particles in the rock, from coarse to fine.

Color and CompositionRocks can be further identified by their color and either their mineral composition (in igneous and metamorphic rocks) or their particle composition (in sedimentary rocks). Composition affects the color and other properties of a rock.

For example, igneous rocks are divided into two categories—mafic and feslic (or sialic)—based on their composition. Mafic rocks, such as basalt, obsidian, and gabbro, are rich in iron, magnesium, and calcium and are dark in color. Felsic rocks, such as granite, pumice, and rhyolite, are rich in silica and aluminum and are lighter in color.

The composition of the particles—whether they’re quartz, clay, calcite, or shell fragments—are of primary importance in determining the type and properties of sedimentary rock.

For metamorphic rocks, the color patterns and mineral composition suggest the name of the rock and provide information about the conditions under which the rock was formed. Foliated metamorphic rocks, such as gneiss, show banding, or alternating layers of dark and light minerals, and some of the unfoliated metamorphic rocks, such as marble, quartzite, and anthracite coal are comprised of single minerals.

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Date: _________________________________________

Igneous Rocks

Igneous rocks form when melted rock

(lava or magma) cools above ground

or underground. They look different

depending on how fast they cool and

what minerals they contain.

Here are some clues to help you identify igneous rocks.

1. Someigneousrocksformwhenlavaflowsattheearth’ssurface

and cools quickly. Rapid cooling causes the minerals in these rocks

to form tiny crystals or natural glass. These rocks may look shiny

or glassy.

2. Some igneous rocks form when magma cools slowly deep inside the

earth. These rocks may look sparkly because the minerals in them

had plenty of time to form large crystals.

3. Some igneous rocks have lots of air holes that make them

lightweight rocks. Air bubbles trapped in the cooling lava made

these holes.

Igneous Rocks (Lesson 3)

Date: ______________________________________

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Sedimentary Rocks

Sedimentary rocks form when

fragments of rocks, shells, sand

and clay settle at the bottom of

a lake or ocean, and are slowly

pressed and cemented together.

Here are some clues to help you identify sedimentary rocks.

1. Most sedimentary rocks are soft. Some can be crumbled,

split, or broken with your hands.

2. If the rock has big fragments of naturally shaped shells

and pebbles, it is a sedimentary rock.

3. Sedimentary rocks can have distinct layers. Sometimes

these layers have different colors or textures.

4. Ifyoufindafossil in a rock, you can almost be certain that

it is a sedimentary rock.

Sedimentary Rocks (Lesson 3)

�

Date: _________________________________________

Metamorphic Rocks

Metamorphic rocks form when other

rocks are changed by heat and pressure

deep inside the earth. Sometimes

new mineral crystals form as the rock

changes. Sometimes existing minerals are

softened and reshaped.

Here are some clues to help you identify metamorphic rocks.

1. Metamorphic rocks are very hard. Pressure and heat

gradually changed the original rock into much harder

metamorphic rock. For example a hard and brittle

metamorphic rock called “slate” formed from a softer

sedimentary rock made from clay called “shale.”

2. Some metamorphic rocks have stripes or bands.

3. Some metamorphic rocks contain pebbles that were

flattened and stretched by pressure deep inside Earth.

Metamorphic Rocks (Lesson 3)

16 | ROCKS | CONTENT RUBRICS AND OPPORTUNITIES OVERVIEWS

Rubric 1: Properties of Rocks and Minerals Criterion A(Lessons 1 3, 11)

Criterion B (Lessons 4—6, 11)

Criteria C and E (Lessons 4 5, 11)

Criterion D(Lessons 3, 11)

Rocks differ in a wide range of properties,including size, shape, color and texture.

Minerals differ in a wide range of properties,including size, shape, color and texture, hardness, and streak.

Rocks are made of minerals. A rock’s properties result in part from the minerals it is made of.

A rock’s properties result, in part, from how it was formed.

4 - Exceeds Expectations

Explores content beyond the level presented in the lessons.

Understands at a secure level (see box below) and contemplates why rocks have these differentproperties.

Understands at a secure level (see box below) and contemplates why minerals have these differentproperties.

Understands at a secure level (see box below) and shows interest in exploring and identifyingdifferent minerals within rocks.

Understands at a secure level (see box below) and shows interest in further exploring the ways rocks were formed.

3 - Secure (Meets Expectations)

Understandscontent at the level presented in the lessons.

Understands that different rocks have different properties and considers a wide range of properties when describing rocks (for example, size, shape, texture, and color).

Understands that different minerals have different properties and considers a wide range of properties when describing minerals (for example, size, shape, texture, color, hardness, and streak).

Understands that all rocks are made of minerals and that a rock’s properties result, in part, from the minerals they are made of.

Understands that a rock’s properties result, in part, from how it was formed.

2 - Developing(Approaches Expectations)

Shows an increasing competencywith lesson content.

Recognizes that rocks have differentproperties but onlyconsiders a few properties, such as shape and size.

Recognizes that minerals have different properties but only considers a few properties, such as shape and size.

Knows that rocks are made of minerals but doesn’t relate how the properties of rocks are a result of the properties of minerals.

Understands that rocks form in different ways but doesn’t relate rock formation to properties. (For example, knows that a rock can be formed from intense heat, but doesn’t know how heat effects how shiny a rock is.)

1 - Beginning

Has no previous knowledge of lesson content.

Does not recognize that rocks can have different properties.

Does not recognize that minerals can have different properties.

Does not know that rocks are made of minerals.

Does not understand how rock formation results in different properties.

ROCKS | CONTENT RUBRICS AND OPPORTUNITIES OVERVIEWS | 17

Opportunities Overview: Properties of Rocks and Minerals

This table highlights opportunities to assess the criteria on Rubric 1: Properties of Rocks and Minerals. It does not include every assessment opportunity; feel free to select or devise other ways to assess various criteria.

Criterion A(Lessons 1 3, 11)

Criterion B (Lessons 4 6, 11)

Criteria C and E (Lessons 4 5, 11)

Criterion D (Lesson 3, 11)

Pre

and

Form

ativ

e

Opp

ortu

nitie

s

Lesson 1: - Family Link “Rock

Hound”Lesson 2: - Sensory observation - Reflective

discussion- Science notebook

pages 4-5 Lesson 3: - Exploration

Lesson 4: - Science notebook

page 9 - Reflective

discussionLesson 5: - Exploration - Science notebook

page 10 - Reflective

discussionLesson 6: - Science notebook

page 11 - Reflective

discussion

Lesson 4: - Exploration - Science notebook

page 9 - Reflective

discussionLesson 5: - Reflective

discussion

Lesson 3: - Exploration - Reflective

discussion

Performance Tasks

Describing Rocks Cluster“Guess My Rock,”

page 26 Lesson 11 “My Special Rock

Book,” page 31

Rocks and Minerals Cluster“Guess My Mineral,”

page 27 Describing a Mineral,

page 28 Rocks and Minerals,

page 29 Lesson 11 “My Special Rock

Book,” page 31

Rocks and Minerals Cluster“Guess My

Mineral,” page 27

Describing a Mineral, page 28

Rocks and Minerals, page 29

Lesson 11 “My Special Rock

Book,” page 31

Describing Rocks Cluster“Guess My Rock,” page 26

Lesson 11 “My Special Rock Book,” page 31

Quick Check Items

Sum

mat

ive

Opp

ortu

nitie

s

Describing Rocks ClusterPage 34: items 1, 2

Rocks and Minerals ClusterPage 35: items 1, 3-5

Rocks and Minerals ClusterPage 35: items 2, 3-5

Describing Rocks ClusterPage 34: item 2

Rocks and Minerals ClusterPage 35, item 2

22 | ROCKS | CHECKLISTS AND SELF-ASSESSMENTS

Checklist: Observing and DescribingTeacher Assessment

(All Lessons)

Determine whether the following skills are evident as the child makes observations and descriptions. You might want to assign one point for each criterion that the child demonstrates. You can add specific observations or comments in the space below each criterion.

Name Date

Criteria:

A. Observations, descriptions, and drawings are accurate; they reflect actual properties or events.

B. Observations, descriptions, and drawings incorporate details.

C. Uses multiple perspectives when making observations.

ROCKS | CHECKLISTS AND SELF-ASSESSMENTS | 23

Name Date

Self–Assessment: Observing and Describing

Think about your observations, descriptions, and scientific drawings. Answer the following questions.

1. Do you make careful observations?

Always Sometimes Seldom

2. How much detail do you include in your observations, drawings, or descriptions?

A lot of detail Some detail Very little detail

Give some examples of how you included details:

3. Do you use more than one sense when you make observations?

Always Sometimes Seldom

Give some examples of when you used different senses in your observations:

26 | ROCKS | PERFORMANCE TASK EVALUATION GUIDELINES

“Guess My Rock” Describing Rocks Cluster (Lessons 1 3 and 11)

Game Directions:

1. Choose a rock without letting the other players see it.

2. Write a detailed description of your rock at the bottom of this page or on an index card.

3. Put your rocks in a pile with the other players’ rocks.

4. Trade your rock description with another player.

5. Try to find the rock that is described on the page or the index card you are holding.

TEACHER NOTES:Use this assessment after teaching Lesson 3.

Play the “Guess My Rock” game with small groups of children so you can better evaluate their understanding of the properties that differentiate rocks.

You might lead this game or have children read the directions themselves to play the game.

You might also have children use rocks they collected themselves, or have them use rocks from the ExploraGear.

(Optional) To get a more complete picture of children’s understanding of a rock’s properties, you might select one or two rocks from the pile after the game and have the children discuss properties that help identify how the rock was formed and what it’s general classification is (metamorphic, igneous, or sedimentary).

EVALUATION GUIDELINES:Consider the following elements when evaluating children’s descriptions and identification techniques:

Do children use more than one or two properties to describe their rock?

Do children focus on the properties when trying to identify other rocks in the pile?

(Optional) Do children focus on properties to attempt to discover how the rock was formed? When evaluating this particular concept, the emphasis should be on the characteristics children use to help them identify how the rock was formed, not on if they correctly identify the rock classification type (metamorphic, igneous, or sedimentary).

34 | ROCKS | QUICK CHECK ANSWER KEYS

Describing Rocks Cluster Quick Check Items

TEACHER NOTE: The following questions relate to the Describing Rocks cluster. Use them after teaching the entire cluster, or select the applicable questions immediately following each lesson. You can also compile the Quick Check items into an end-of-unit assessment.

1. (Lesson 2) Put an “X” next to any words that are useful for describing rocks.

color X

size X

texture X

smell X

weight X

2. (Lesson 3) MATCHING: Draw lines to match the rock clue to rock type.

ROCK CLUES ROCK TYPES

This rock is usually soft. Fossils are often found in this rock. igneous rock Sometimes this rock has big pieces of shells and pebbles in it.

This rock is very hard. Pressure and heat changed this sedimentary rock rock to make it hard.

This rock forms from lava or magma. Sometimes this rock is lightweight because metamorphic rock it has lots of air holes.

40 | ROCKS | ASSESSMENT MASTERS

Name Date

“Guess My Rock” Game Directions:

1. Choose a rock without letting the other players see it.

2. Write a detailed description of your rock at the bottom of this page or on an index card.

3. Put your rocks in a pile with the other players’ rocks.

4. Trade your rock description with another player.

5. Try to find the rock that is described on the page or the index card you are holding.

ROCKS | ASSESSMENT MASTERS | 41

Name Date

Describing RocksQuick Check Items

1. Put an “X” next to any words that are useful for describing rocks.

color

size

texture

smell

weight

2. MATCHING: Draw lines to match the rock clue to rock type.

ROCK CLUES ROCK TYPES

This rock is usually soft. Fossils are often found in this rock. igneous rock Sometimes this rock has big pieces of shells and pebbles in it.

This rock is very hard. Pressure and heat changed this sedimentary rock rock to make it hard.

This rock forms from lava or magma. Sometimes this rock is lightweight because metamorphic rock it has lots of air holes.

Rocks Teacher Master ��

Igneous Rocks

Igneous rocks form when melted

rock (lava or magma) cools above

ground or underground . They look

different depending on how fast

they cool and what minerals they

contain .

Here are some clues to help you identify igneous rocks.

1 . Some igneous rocks form when lava flows at the earth’s surface and

cools quickly . Rapid cooling causes the minerals in these rocks to form

tiny crystals or natural glass . These rocks may look shiny or glassy .

2 . Some igneous rocks form when magma cools slowly deep inside the

earth . These rocks may look sparkly because the minerals in them had

plenty of time to form large crystals .

3 . Some igneous rocks have lots of air holes that make them lightweight

rocks . Air bubbles trapped in the cooling lava made these holes .

Teacher Master: Igneous Rocks (Lesson �)

Rocks Teacher Master ��Teacher Master: Sedimentary Rocks (Lesson �)

Sedimentary Rocks

Sedimentary rocks form when

fragments of rocks, shells, sand and clay

settle at the bottom of a lake or ocean,

and are slowly pressed and cemented

together .

Here are some clues to help you identify sedimentary rocks.

1 . Most sedimentary rocks are soft . Some can be crumbled, split, or

broken with your hands .

2 . If the rock has big fragments of naturally shaped shells and pebbles,

it is a sedimentary rock .

3 . Sedimentary rocks can have distinct layers . Sometimes these layers

have different colors or textures .

4 . If you find a fossil in a rock, you can almost be certain that it is a

sedimentary rock .

Rocks Teacher Master ��Teacher Master: Metamorphic Rocks (Lesson �)

Metamorphic Rocks

Metamorphic rocks form when other

rocks are changed by heat and pressure

deep inside the earth . Sometimes new

mineral crystals form as the rock changes .

Sometimes existing minerals are softened

and reshaped .

Here are some clues to help you identify metamorphic rocks.

1 . Metamorphic rocks are very hard . Pressure and heat gradually changed

the original rock into much harder metamorphic rock . For example a

hard and brittle metamorphic rock called “slate” formed from a softer

sedimentary rock made from clay called “shale .”

2 . Some metamorphic rocks have stripes or bands .

3 . Some metamorphic rocks contain pebbles that were flattened and

stretched by pressure deep inside Earth .

Rocks Teacher Master ��

Rock CluesIgneous Rocks

Read the description in each box and place any rocks that match that

description inside the box . Repeat for each box .

Teacher Master: Rock Clues—Igneous Rocks (Lesson �)

These rocks look shiny and glassy .

These rocks have large crystals that make them look sparkly .

These rocks are much lighter than they appear .

Rocks Teacher Master ��Teacher Master: Rock Clues—Sedimentary Rocks (Lesson �)

Rock CluesSedimentary Rocks

Read the description in each box and place any rocks that match that

description inside the box . Repeat for each box .

We can break off a tiny piece of these rocks .

We can see pebbles and pieces of shells in these rocks .

We can see layers in these rocks .

Rocks Teacher Master ��Teacher Master: Rock Clues—Metamorphic Rocks (Lesson �))

Rock CluesMetamorphic Rocks

Read the description in each box and place any rocks that match that

description inside the box . Repeat for each box .

We can see flattened pebbles in these rocks .

We can see stripes in these rocks .

These rocks are very, very, hard .

Rocks Teacher Master ��

Rock LabelsIgneous Rocks

Teacher Master: Rock Labels—Igneous Rocks (Lesson �)

M.Basalt

N.Obsidian

O.Rhyolite

P.Granite

S.Scoria

W.Pumice

X.Porphyry

Rocks Teacher Master ��Teacher Master: Rock Labels—Sedimentary Rocks (Lesson �)

Rock LabelsSedimentary Rocks

Q.Sandstone

T.Limestone

Y.Shale

Z.Conglomerate

Rocks Teacher Master ��Teacher Master: Rock Labels—Metamorphic Rocks (Lesson �)

Rock LabelsMetamorphic Rocks

L.Marble

R.Slate

U.Gneiss

V.Metaconglomerate

2011 Edition. Copyright © 2004 Chicago Science Group.All rights reserved. Except as permitted under the United States Copyright Act no part of this publication may be reproduced or

distributed in any form or by any means or stored in a database or retrieval system without the prior written permission of the publisher.

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DoingScience

“I Wonder” Circle®

Doing Science

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I Wonder: notice, ask questions, state problems I Think: consider, gather information, predict I Try: experiment, model, test ideas, repeat I Observe: watch, examine, measure I Record: record data, organize, describe, classify, graph, draw I Discover: look for patterns, interpret, reflect, conclude, communicate discoveries