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The following instructional plan is part of a GaDOE collection of Unit Frameworks, Performance Tasks, examples of Student
Work, and Teacher Commentary. Many more GaDOE approved instructional plans are available by using the Search Standards
feature located on GeorgiaStandards.Org.
Georgia Performance Standards Framework for Earth Science – Grade 6
Unit: Rocks and Minerals
General Task
How Are Rocks Identified?
Standards (Content and Characteristics):
S6E5. Students will investigate the scientific view of how the earth’s surface is formed.
b. Investigate the contribution of minerals to rock composition.
c. Classify rocks by their process of formation.
d. Describe processes that change rocks and the surface of the earth.
S6CS1. Students will explore the importance of curiosity, honesty, openness, and
skepticism in science and will exhibit these traits in their own efforts to understand how the
world works.
a. Understand the importance of—and keep—honest, clear, and accurate records in science.
S6CS6. Students will communicate scientific ideas and activities clearly.
c. Organize scientific information using appropriate tables, charts, and graphs, and identify
relationships they reveal.
S6CS2. Students will use standard safety practices for all classroom laboratory and field
investigations.
a. Follow correct procedures for use of scientific apparatus.
b. Demonstrate appropriate techniques in all laboratory situations.
c. Follow correct protocol for identifying and reporting safety problems and violations
Enduring Understanding:
Rocks are classified based on how they formed and their mineral composition.
Sedimentary rocks are formed by the ongoing deposition of rocks and other sediments
that are cemented together.
Rocks at the surface of the Earth weather, forming sediments that are buried, then
compacted, heated, and often re-crystallize into new rock.
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Earth Science  Grade 6  Rocks and Minerals
July 26, 2007 Page 1 of 10
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Earth Science – Grade 6
Essential Questions:
How are rocks formed?
How are rocks classified?
ADMINISTRATION PROCEDURES
Pre-Assessment:
Put rocks at various stations. Ask students to identify the rocks. Provide students with a blank
answer document to record responses. Students will move from station to station and identify as
many rocks as possible using visual observations.
Outcome /
Performance
Expectations:
General Teacher
Instructions:
Materials
Needed:
Students will be able to identify common igneous, sedimentary, and
metamorphic rocks.
Students will interpret the process of formation of rocks by looking at their
textures.
Obtain mineral and rock specimens from scientific supply house, from gem
and mineral show, or by collecting them. Local mineral societies may also
have materials which they can donate.
Rocks that the students will identify might include the following as
examples of
IGNEOUS ROCKS:
o Granite
o Gabbro
o Diorite
o Basalt
o Rhyolite
o Andesite
o Pumice
o Scoria
o Obsidian
SEDIMENTARY ROCKS:
o Sandstone
o Limestone
o Rock gypsum
o Shale
o Conglomerate
o Breccia
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Earth Science  Grade 6  Rocks and Minerals
July 26, 2007 Page 2 of 10
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Earth Science – Grade 6
Safety
Precautions:
Task with
Student
Directions:
METAMORPHIC ROCKS:
o Slate
o Mica schist
o Gneiss
o Marble
o Quartzite
Students should wear safety goggles.
Students should wash hands at the conclusion of the activity.
Background information on Rocks
A rock is an aggregate of one or more minerals
There are three basic categories of rocks:
Igneous (or cooled from hot molten lava or magma) - ex. granite,
basalt
Sedimentary (or fragments laid down by water or wind) - ex.
sandstone, shale, limestone
Metamorphic (or rocks changed by heat and or pressure) - ex.
gneiss, schist, slate, marble
Rocks are the building blocks of the Earth's crust.
We can identify the minerals present in rocks. We can learn about the
process of formation of rocks by looking at their textures (or grain sizes,
shapes, and arrangement).
I. IGNEOUS ROCKS
Igneous rocks are "fire-formed". They crystallized from hot, molten lava or
magma as it cooled. Magma is hot, molten rock beneath the surface of the
Earth. Lava is hot, molten rock which has flowed out onto the surface of
the Earth. Magma may cool within the Earth's crust to form igneous rocks.
But lava cools much more quickly because it is on the Earth's surface where
temperatures are much lower than they are deep within the Earth.
Cooling rates influence the texture of the igneous rock:
Quick cooling = fine grains
Slow cooling = coarse grains
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Earth Science  Grade 6  Rocks and Minerals
July 26, 2007 Page 3 of 10
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Earth Science – Grade 6
Igneous rocks are classified (or named) based on their composition (which
minerals they contain) and texture (or the size of the mineral grains). The
texture is a result of the process of formation of the igneous rocks.
A variety of textures are present in igneous rocks. For this exercise, we will
only consider a few textures (and their process of formation):
Fine-grained (produced by quick cooling and crystallization of lava),
Coarse-grained (produced by slow cooling and crystallization of lava),
Glassy (produced by instantaneous cooling of lava – so fast that there is no
time for minerals to crystallize), and
Vesicular (contains holes made by gas bubbles in a quick-cooling or
instantaneous-cooling lava).
Now and then, you may see an igneous rock with a mixture of grain sizes –
larger minerals surrounded by smaller minerals. This indicates a
complicated process of formation of the igneous rock, in which the magma
initially cooled very slowly, and then the magma erupted as lava and cooled
quickly. An igneous rock with mixed grain size indicates a mixed cooling
history.
Part A. Examining the minerals in coarse-grained igneous rocks.
Examine granite, diorite and gabbro with the magnifying glass or
microscope.
Describe the appearance of at least two minerals you can see in each rock.
Igneous
Rock
Granite
Describe two physical properties
of the rock
Diorite
Gabbro
Part B. Examining the minerals and textures of igneous rocks
Examine the igneous rocks listed in the table below. Tell whether their
minerals are visible and readily seen with the naked eye (coarse grained), or
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Earth Science  Grade 6  Rocks and Minerals
July 26, 2007 Page 4 of 10
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Earth Science – Grade 6
whether they are too small to identify (fine grained), or whether the texture
is glassy, vesicular (bubbles) or mixed. Then interpret the process of
formation of the igneous rock.
Igneous
Rock
Texture
(fine-grained, coarsegrained, glassy, vesicular,
or mixed)
Process of formation
(fast cooling, slow cooling,
instantaneous cooling, gas
bubbles released during
cooling, or mixed cooling
history)
Obsidian
Pumice
Scoria
Granite
Rhyolite
Diorite
Andesite
Basalt
Gabbro
II. SEDIMENTARY ROCKS
Sedimentary rocks are made from sediment. Sediment is loose particulate
material (clay, sand, gravel, shells, plant fragments, etc.). Sediment may be
transported and deposited by moving water, wind, or ice. Sediment
becomes compacted and cemented to form sedimentary rock.
We can interpret the process of formation of sedimentary rocks by looking
at their grain size and shape (i.e., their texture). Fine-grained sedimentary
rocks were deposited by still, quiet, low-energy water. Coarse-grained
sedimentary rocks were deposited by rapidly-moving, high-energy water.
We can also look at the shapes of the grains in sedimentary rocks to learn
about their process of formation. Rounded grains in a sedimentary rock
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Earth Science  Grade 6  Rocks and Minerals
July 26, 2007 Page 5 of 10
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Earth Science – Grade 6
indicate a long distance of transportation during which the grains of
sediment rolled and tumbled along, which wore down any sharp corners.
Angular grains in a sedimentary rock indicate a short distance of
transportation.
Part A. Examining the minerals in sedimentary rocks.
Examine the sedimentary rocks listed in the table below. Use a magnifying
glass. Describe physical characteristics of each in the table below.
Answer the questions below.
Sedimentary rock
Sandstone
Describe two physical properties of the rock
Limestone
Rock gypsum
Shale
Part B. Examining the textures of sedimentary rocks
Examine the sedimentary rocks listed in the table below. Use a magnifying
glass. Describe the grain size and then interpret the process of formation,
indicating whether it was deposited by high-energy or low-energy water.
Then in the next table, examine the differences in grain shape in
conglomerate and breccia, and interpret the process of formation in terms of
distance of transport.
Sedimentary
rock
Grain size
Process of formation
(fine-grained or (deposition by high-energy or lowcoarse-grained) energy water)
Conglomerate
Sandstone
Shale
Breccia
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Earth Science  Grade 6  Rocks and Minerals
July 26, 2007 Page 6 of 10
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Earth Science – Grade 6
Sedimentary rock
Grain shape
(angular or
rounded)
Process of formation
(long or short distance of
transport)
Conglomerate
Breccia
III. METAMORPHIC ROCKS
Metamorphic rocks formed as a result of changes to other types of rocks.
The processes of formation of metamorphic rocks involve changes caused
by heat and pressure associated with deep burial and tectonic pressures
(caused by moving tectonic plates). Those changes, called metamorphism,
include compaction (which makes the rock become more dense and makes
the grains move closer together), and recrystallization (the growth of new
minerals). In other words, metamorphism causes changes in the texture and
minerals of rocks.
As shale is subjected to increasing heat and pressures, the clay minerals in it
are recrystallized to form micas (such as muscovite and biotite). As heat
and pressure increase, the mica grains increase in size.
Pressure causes the minerals in a metamorphic rock to become oriented
perpendicular to the direction of force. The mica grains (such as muscovite
and biotite) become aligned parallel with one another to form a new texture
called foliation. Rocks with foliation include slate, schist and gneiss.
Metamorphic rocks which lack mica minerals are called non-foliated, and
they have an even, granular texture with no aligned minerals. Non-foliated
metamorphic rocks include marble and quartzite.
Part A. Examining minerals in metamorphic rocks.
Examine the metamorphic rocks listed in the table below. Use a
magnifying glass. Describe the physical properties of each in the table
below.
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Earth Science  Grade 6  Rocks and Minerals
July 26, 2007 Page 7 of 10
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Earth Science – Grade 6
Metamorphic rock
Physical characteristics
Slate
Schist
Gneiss
Marble
Quartzite
Part B. Examining textures in metamorphic rocks.
Examine the metamorphic rocks listed in the table below. Use a
magnifying glass. Look at the textures to determine if the rocks are foliated
or non-foliated.
Metamorphic rock
Texture
(foliated or non-foliated)
Gneiss
Marble
Schist
Quartzite
Slate
Resources:
http://www.minsocam.org/MSA/K12/K_12.html
http://volcano.und.nodak.edu/vwdocs/vwlessons/rocks.html
http://gpc.edu/~pgore/Earth&Space/GPS/Minerals.html
http://gpc.edu/~pgore/geology/physical_lab/mineral-handy-dandy.htm
http://gpc.edu/~pgore/geology/physical_lab/mineral-fill-in-sheet.htm
http://mineral.galleries.com/minerals/physical.htm#phy
http://www.classzone.com/books/earth_science/terc/content/visualizations/e
s0505/es0505page01.cfm?chapter_no=visualization
http://www.mii.org/
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Earth Science  Grade 6  Rocks and Minerals
July 26, 2007 Page 8 of 10
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Earth Science – Grade 6
Homework /
Extension:
Instructional
Task
Accommodations
for ELL
Students:
Instructional
Task
Accommodations
for Students with
Specific
Disabilities:
Instructional
Task
Accommodations
for Gifted
The Georgia Mineral Society provides mini-grants for teachers to assist
with the purchase of rocks and minerals. See
http://www.gamineral.org/minigrant.htm
The Georgia Mineral Society has a list of retired hobbyist and working
professionals who have agreed to give talks on subjects related to our
hobby. Interested parties may contact GMS at [email protected] and
request a speaker. GMS speakers will review and fulfill these requests as
their individual schedules permit! Learn more about our GMS Speakers
Bureau by following this link: http://www.gamineral.org/speakersbureau.html
Plan a fieldtrip to a local museum that has displays of minerals and rocks,
such as the Weinmann Mineral Museum (TELLUS) in Cartersville.
Identify and locate information on your home state's (or a nearby
state's) state mineral.
You can learn about the state mineral, state gem, and state fossil on this web
page.
See also http://www.cviog.uga.edu/Projects/gainfo/mineralresn.htm
Work with a student with strong English language skills
Highlight key points in the article
Reduce the number of key points these students are responsible for
knowing
Extend the time to complete the task
Seat student near teacher or positive role model during direct instruction
and student centered activity time
Adjust teacher talk to increase comprehensibility during direct
instruction and while conveying task directions
Speak carefully and avoid slang terms or unfamiliar idiomatic
experience
Describe the characteristics of the rocks for visually impaired students
Break work into manageable parts
Reinforce oral instructions with written instructions
Graphically display an analysis of the expected task including a
checklist to facilitate attention to task and organizational skills
Assess informally on an on-going basis
Use alternative assessments
Have gifted students use rock identification keys from the web or from a
book to identify minerals and rocks. Give them unlabeled rocks to
identify.
Students use common mineral testing techniques to identify the actual
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Earth Science  Grade 6  Rocks and Minerals
July 26, 2007 Page 9 of 10
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Earth Science – Grade 6
Students:
mineral composition of the rocks used as examples.
Provide digital microscopes to examine the rocks. Have the gifted
students take digital images of the rocks and prepare a computer
presentation for the class indicating how each of the rocks formed.
Allow role plays and scenarios.
Offer choices and chunk concepts for students.
Problem-based Learning Activities.
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Earth Science  Grade 6  Rocks and Minerals
July 26, 2007 Page 10 of 10
Copyright 2007 © All Rights Reserved