district of columbia public schools science standards, grade 6 · unit 1 earth’s surface ......

correlated to

District of ColumbiaPublic Schools

Science Standards,Grade 6


Science Standards, Grade 6

correlated to

McDougal Littell Earth Science

TABLE OF CONTENTS

Correlation……………………………………………………………………………….1

District of Columbia Public Schools Science Standards, Grade 6……….…………16

1


Science Standards, Grade 6

correlated to

McDougal Littell Earth Science

McDougal Littell Earth Science DCPS Science Content StandardsGrade 6

Unifying Principles of Earth Sciencepp. xxix–xxxvii

Introduction to 6.3.6, 6.3.10, 6.4.1, 6.5.5,6.8.12, 6.9.4, 6.9.7

The Nature of Sciencepp. xxxviii–xli

6.1.1, 6.2.1, 6.2.7

The Nature of Technologypp. xlii–xliii

6.1.1, 6.2.2

UNIT 1 EARTH’S SURFACEFrontiers in Science, Remote Sensing

pp. 2–56.1.1, 6.1.9, 6.2.2, 6.4.1

Chapter 1Views of Earth Today, pp. 6–391.1Technology is used to explore the Earth

system.pp. 9–14

6.1.1, 6.2.2, 6.5.2, 6.9.1, 6.9.3

1.2Maps and globes are models of Earth.

pp. 15–23

6.1.9, 6.1.10, 6.2.1, 6.2.2

1.3Topographic maps show the shape of the

land. pp. 24–27

6.1.9

Chapter Investigation pp. 28–29

6.1.5, 6.1.9, 6.1.10

1.4Technology is used to map Earth.

pp. 30–35

6.1.1, 6.1.8, 6.2.1, 6.2.2

Chapter 1 Review/Standardized TestPractice

pp. 36–39

6.1.8, 6.1.9, 6.2.1, 6.2.2

District of Columbia Public Schools Science Standards, Grade 6 correlated toMcDougal Littell Earth Science ©2006

2


Chapter 2Minerals, pp. 40–712.1Minerals are all around us.

pp. 43–49

6.1.1, 6.1.8, 6.7.1, 6.7.2

2.2A mineral is identified by its properties.

pp. 50–57

6.1.1, 6.1.8, 6.7.1, 6.7.2

Chapter Investigationpp. 58–59

6.1.1, 6.1.5, 6.1.8, 6.7.1

2.3Minerals are valuable resources.

pp. 60–67

6.7.1


pp. 68–71

6.1.8, 6.7.1, 6.7.2

Chapter 3Rocks, pp. 72–1073.1The rock cycle shows how rocks change.

pp. 75–81

6.1.1, 6.1.6, 6.7.2, 6.7.3, 6.7.4, 6.7.5, 6.9.2,6.9.7

3.2Igneous rocks form from molten rock.

pp. 82–88

6.1.4, 6.1.8, 6.7.2, 6.7.3, 6.7.6, 6.9.1

3.3Sedimentary rocks form from earlier rocks.

pp. 89–95

6.7.5, 6.9.1, 6.9.4, 6.9.5

3.4Metamorphic rocks form as existing rockschange.

pp. 96–101

6.7.4, 6.7.9, 6.9.1


6.1.1, 6.1.5, 6.1.8, 6.7.2, 6.7.6


pp. 104–107

6.1.8, 6.7.2, 6.7.3, 6.7.4, 6.7.5, 6.8.12, 6.9.7

Timelines in Science History of the EarthSystem

pp. 108–111

6.1.1, 6.1.6, 6.2.2, 6.3.1, 6.3.10, 6.8.12,6.9.2, 6.9.4, 6.9.6


3


Chapter 4Weathering and Soil Formation, pp. 112–1414.1Mechanical and chemical forces break downrocks.

pp. 115–121

6.1.1, 6.9.1

4.2Weathering and organic processes form soil.

pp. 122–129

6.9.1, 6.9.3


6.1.1, 6.1.2, 6.1.5, 6.9.3

4.3Human activities affect soil.

pp. 132–137

6.1.1, 6.2.1, 6.6.3, 6.9.1


pp. 138–141

6.1.1, 6.1.8, 6.9.1, 6.9.3

Chapter 5Erosion and Deposition, pp.142–1755.1Forces wear down and build up Earth’ssurface.

pp. 145–149

6.1.1, 6.1.2, 6.1.3, 6.1.5, 6.1.7, 6.3.10, 6.9.1,6.9.3

5.2Moving water shapes land.

pp. 150–155

6.9.1


6.1.1, 6.1.5, 6.9.1

5.3Waves and wind shape land.

pp. 158–164

6.1.1, 6.1.6, 6.9.1, 6.9.3

5.4Glaciers carve land and move sediments.

pp. 165–171

6.1.1, 6.1.2, 6.5.1, 6.9.1


pp. 172–175

6.9.1


4


UNIT 2 THE CHANGING EARTHFrontiers in Science, Studying Volcanoeswith Satellites

pp. 178–181

6.1.1, 6.1.6, 6.2.2, 6.9.2

Chapter 6Plate Tectonics, pp. 182–2176.1Earth has several layers.

pp. 185–189

6.1.1, 6.8.1, 6.8.2, 6.8.4, 6.9.6

6.2Continents change position over time.

pp. 190–195

6.1.1, 6.2.2, 6.4.1, 6.8.3, 6.8.10, 6.9.7, 6.9.6,6.9.7


6.1.1, 6.1.3, 6.1.4, 6.1.5, 6.4.1

6.3Plates move apart.

pp. 198–205

6.1.1, 6.2.2, 6.8.3, 6.9.4, 6.9.6

6.4Plates converge or scrape past each other.

pp. 206–213

6.1.1, 6.1.2, 6.8.3, 6.8.4, 6.8.5, 6.8.7, 6.8.9,6.1.1, 6.1.7, 6.8.9, 6.8.10, 6.8.11, 6.9.4


pp. 214–217

6.1.1, 6.1.7, 6.8.1, 6.8.3, 6.8.5, 6.8.6, 6.8.7,6.8.9, 6.8.10, 6.8.11


5


Chapter 7Earthquakes, pp. 218–2497.1Earthquakes occur along faults.

pp. 221–226

6.1.1, 6.8.1, 6.8.3, 6.8.8, 6.8.9

7.2Earthquakes release energy.

pp. 227–235

6.1.1, 6.1.9, 6.2.2, 6.8.5

7.3Earthquake damage can be reduced.

pp. 236–243

6.1.1, 6.1.9, 6.2.1, 6.2.2, 6.8.8


6.1.1, 6.1.5, 6.1.7, 6.1.8


pp. 246–249

6.1.7, 6.1.8, 6.8.1, 6.8.3, 6.8.5, 6.8.8, 6.8.9

Chapter 8Mountains and Volcanoes, pp. 250–2838.1Movement of rock builds mountains.

pp. 253–261

6.1.1, 6.8.3, 6.8.7

8.2Volcanoes form as molten rock erupts.

pp. 262–269

6.1.1, 6.2.1, 6.2.2, 6.8.6, 6.8.8, 6.8.10


6.1.1, 6.1.3, 6.1.5, 6.1.7, 6.1.8

8.3Volcanoes affect Earth’s land, air, andwater.

pp. 272–279

6.1.1, 6.5.5, 6.6.5, 6.8.6, 6.8.11, 6.9.2


pp. 280–283

6.1.1, 6.1.7, 6.1.8, 6.5.5, 6.6.5, 6.8.6, 6.8.7,6.8.8, 6.8.9, 6.8.10, 6.8.11, 6.9.2


6


Chapter 9Views of Earth’s Past, pp. 284–3159.1Earth’s past is revealed in rocks and fossils.

pp. 287–294

6.1.1, 6.1.7, 6.2.1, 6.2.2, 6.8.12, 6.9.7

9.2Rocks provide a timeline for Earth. pp. 295–302

6.1.1, 6.1.8, 6.2.2, 6.8.12, 6.9.4, 6.9.5, 6.9.6

9.3The geologic time scale shows Earth’s past.

pp. 303–309

6.1.1, 6.2.2, 6.5.5, 6.8.12, 6.9.2, 6.9.4, 6.9.6,6.9.7


6.1.1, 6.1.5, 6.1.8, 6.9.6, 6.9.7


pp. 312–315

6.1.7, 6.1.8, 6.8.12, 6.9.2, 6.9.4, 6.9.5, 6.9.6,6.9.7

Timelines in Science The Story of Fossilspp. 316–319

6.1.1, 6.1.7, 6.2.1, 6.2.2, 6.8.12, 6.9.4, 6.9.5,6.9.6, 6.9.7

Chapter 10Natural Resources, pp. 312–34910.1Natural resources support human activity.

pp. 323–331

6.1.1, 6.1.6, 6.6.1, 6.6.2, 6.6.3, 6.6.5

10.2Resources can be conserved and recycled.

pp. 332–336

6.1.1, 6.1.2, 6.1.3, 6.1.5, 6.6.6

10.3Energy comes from other natural resources.

pp. 337–345

6.2.2, 6.6.3


6.1.1, 6.1.3, 6.1.5, 6.1.8


pp. 348–351

6.1.1, 6.1.7, 6.1.8, 6.6.3, 6.6.6


7


UNIT 3 EARTH’S WATERSFrontiers in Science Exploring the WaterPlanet

pp. 354–357

6.1.1, 6.1.7, 6.2.2, 6.4.4, 6.6.7

Chapter 11The Water Planet, pp. 358–38911.1Water continually cycles.

pp. 361–367

6.1.1, 6.1.2, 6.1.4, 6.1.5, 6.1.6, 6.1.7, 6.6.1,6.6.3, 6.6.8

11.2Fresh water flows and freezes on Earth. pp. 368–375

6.6.1, 6.6.7, 6.6.8

11.3Fresh water flows underground.

pp. 376–383

6.1.1, 6.6.1


6.1.1, 6.1.2, 6.1.4, 6.1.5, 6.1.7, 6.1.8, 6.6.6


pp. 386–389

6.1.1, 6.1.8, 6.6.1, 6.6.2, 6.6.3, 6.6.6, 6.6.8

Chapter 12Freshwater Resources, pp. 390–42312.1Fresh water is an essential resource.

pp. 393–401

6.1.1, 6.1.6, 6.6.1, 6.6.2, 6.6.3

12.2Society depends on clean and safe water.

pp. 402–409

6.2.2, 6.6.1, 6.6.2, 6.6.3


6.1.1, 6.1.3, 6.1.5, 6.1.8, 6.2.2, 6.6.2

12.3Water shortages threaten society.

pp. 412–419

6.1.1, 6.6.1, 6.6.2, 6.6.3


pp. 420–423

6.1.7, 6.1.8, 6.6.1, 6.6.2, 6.6.3


8


Chapter 13Ocean Systems, pp. 424–45713.1The oceans are a connected system.

pp. 427–435

6.1.1, 6.1.8, 6.2.2

13.2Ocean water moves in currents.

pp. 436–440

6.1.1, 6.5.1, 6.5.2

13.3Waves move through oceans.

pp. 441–445Chapter Investigation

pp. 446–4476.1.1, 6.1.5, 6.1.7, 6.1.8

13.4Waters rise and fall in tides.

pp. 448–453

6.1.1, 6.1.7, 6.3.10


pp. 454–457

6.1.1, 6.1.7, 6.1.8, 6.3.10, 6.5.2

Timelines in Science, Exploring the Oceanpp. 458–461

6.1.1, 6.2.2, 6.6.2, 6.6.5

Chapter 14Ocean Environments, pp. 462–49514.1Ocean coasts support plant and animal life.

pp. 465–472

6.1.1, 6.1.2, 6.1.3, 6.1.5, 6.1.7, 6.1.8, 6.6.1,6.6.2, 6.6.4

14.2Conditions differ away from shore.

pp. 473–481

6.1.1, 6.1.2, 6.1.5, 6.1.7

14.3The ocean contains natural resources.

pp. 482–489

6.6.4


6.1.1, 6.1.5, 6.1.8


pp. 492–495

6.1.7, 6.1.8


9


UNIT 4 EARTH’S ATMOSPHEREFrontiers in Science, Dust in the Air

pp. 498–5016.1.1, 6.1.2, 6.1.5, 6.1.6, 6.1.8, 6.2.2

Chapter 15Earth’s Changing Atmosphere, pp. 502–53515.1Earth’s atmosphere supports life.

pp. 505–511

6.1.1, 6.5.5, 6.5.6

15.2The Sun supplies the atmosphere’s energy.

pp. 512–517

6.1.1, 6.4.1, 6.4.2

15.3Gases in the atmosphere absorb radiation.

pp. 518–522

6.1.1, 6.1.8, 6.4.4

15.4Human activities affect the atmosphere.

pp. 523–529

6.1.8, 6.2.2, 6.6.3, 6.6.4, 6.6.5


6.1.1, 6.1.5, 6.1.8


pp. 532–535

6.1.1, 6.1.7, 6.1.8, 6.4.1, 6.5.6, 6.6.3, 6.6.4,6.6.5


10


Chapter 16Weather Patterns, pp. 536–57116.1The atmosphere’s air pressure changes.

pp. 539–542

6.1.1, 6.2.2, 6.5.6

16.2The atmosphere has wind patterns.

pp. 543–551

6.1.1, 6.4.3, 6.5.2

16.3Most clouds form as air rises and cools.

pp. 552–559

6.1.1, 6.5.3


6.1.1, 6.1.3, 6.1.5, 6.1.7, 6.1.8

16.4Water falls to Earth’s surface as

precipitation.pp. 562–567

6.1.1, 6.1.6, 6.1.7, 6.5.3


pp. 568–571

6.1.7, 6.1.8, 6.5.2, 6.5.3, 6.5.6


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Chapter 17Weather Fronts and Storms, pp. 572–60517.1Weather changes as air masses move.

pp. 575–582

6.1.1, 6.5.2

17.2Low-pressure systems can become storms.

pp. 583–587

6.1.1, 6.5.4

17.3Vertical air motion can cause severe storms.

pp. 588–593

6.1.1, 6.1.4, 6.1.7, 6.5.3

17.4Weather forecasters use advancedtechnologies.

pp. 594–599

6.2.1, 6.2.2


6.1.1, 6.1.2, 6.1.4, 6.1.5, 6.1.6, 6.1.8


pp. 602–605

6.1.7, 6.1.8, 6.5.2, 6.5.3, 6.5.4

Timelines in Science, Observing theAtmosphere

pp. 606–609

6.1.1, 6.2.2, 6.4.3

Chapter 18Climate and Climate Change, pp. 610–63918.1Climate is a long-term weather pattern.

pp. 613–620

6.1.1, 6.1.6, 6.4.5, 6.4.6, 6.5.1, 6.5.4

18.2Earth has a variety of climates.

pp. 621–625

6.4.2, 6.5.1, 6.5.4


6.1.1, 6.1.3, 6.1.4, 6.1.5, 6.1.8

18.3Climates can change suddenly or slowly.

pp. 628–635

6.1.1, 6.1.7, 6.1.8, 6.5.2, 6.5.4, 6.5.5, 6.9.2,6.9.7


pp. 636–639

6.1.7, 6.1.8, 6.4.2, 6.4.5, 6.4.6, 6.5.1, 6.5.4,6.5.5, 6.9.2


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UNIT 5 SPACE SCIENCEFrontiers in Science, Danger from the Sky

pp. 642–6456.1.1, 6.1.6, 6.2.2, 6.5.5, 6.9.2

Chapter 19Exploring Space, pp. 646–67919.1Some space objects are visible to the human

eye.pp. 649–654

6.1.1, 6.3.1, 6.3.5

19.2Telescopes allow us to study space fromEarth. pp. 655–659

6.2.1, 6.2.2


6.1.1, 6.1.5, 6.1.8, 6.2.2

19.3Spacecraft help us explore beyond Earth.

pp. 662–670

6.1.1, 6.2.1, 6.2.2, 6.3.10

19.4Space exploration benefits society.

pp. 671–675

6.1.1, 6.1.6, 6.1.7, 6.2.2, 6.3.10


pp. 676–679

6.1.7, 6.1.8, 6.2.2, 6.3.1, 6.3.5, 6.3.10


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Chapter 20Earth, Moon, and Sun, pp. 680–71120.1Earth rotates on a titled axis and orbits theSun.

pp. 683–689

6.1.1, 6.3.6, 6.3.7, 6.3.11


6.1.1, 6.1.5, 6.1.7, 6.1.8, 6.3.6, 6.3.7

20.2The Moon is Earth’s natural satellite.

pp. 692–698

6.1.1, 6.1.8, 6.3.3, 6.3.7, 6.3.11

20.3Positions of the Sun and Moon affect Earth.

pp. 699–707

6.1.1, 6.3.10, 6.3.11


pp. 708–711

6.1.7, 6.1.8, 6.3.3, 6.3.6, 6.3.7, 6.3.10,6.3.11

Timelines in Science, The Story ofAstronomy

pp. 712–715

6.1.1, 6.2.2, 6.3.1, 6.3.2, 6.3.10, 6.3.11


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Chapter 21Our Solar System, pp. 716–75121.1Planets orbit the Sun at different distances.

pp. 719–724

6.1.1, 6.3.1, 6.3.2, 6.3.10, 6.3.11

21.2The inner solar system has rocky planets.

pp. 725–733

6.1.1, 6.1.7, 6.8.2, 6.8.7, 6.9.1

21.3The outer solar system has four giantplanets.

pp. 734–739

6.1.1, 6.3.11

21.4Small objects are made of ice and rock.

pp. 740–745

6.3.3, 6.3.4


6.1.1, 6.1.2, 6.1.3, 6.1.4, 6.1.5, 6.1.8


pp. 748–751

6.1.1, 6.1.7, 6.3.2, 6.3.3, 6.3.4, 6.3.10,6.3.11


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Chapter 22Stars, Galaxies, and the Universe, pp. 752–78322.1The Sun is our local star.

pp. 755–759

6.3.8


6.1.1, 6.1.3, 6.1.4, 6.1.5, 6.1.8

22.2Stars change over their life cycles.

pp. 762–769

6.1.1, 6.1.8, 6.3.9

22.3Galaxies have different sizes and shapes.

pp. 770–774

6.1.1, 6.1.6, 6.1.7, 6.2.1, 6.3.8

22.4The universe is expanding.

pp. 775–779

6.1.1, 6.2.2, 6.3.2


pp. 780–783

6.1.1, 6.1.7, 6.1.8, 6.2.2, 6.3.8, 6.3.9

Student Resource Handbookpp. R1–R51

6.1.1, 6.1.3, 6.1.4, 6.1.5, 6.1.8

Appendixpp. R52–R75

6.1.9, 6.7.1, 6.7.2, 6.7.3, 6.7.4, 6.7.5, 6.8.1


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District of Columbia Public Schools Science Standards Grade 6

Scientific Thinking and Inquiry6.1. Broad Concept: Scientific progress is made by asking relevant questions andconducting careful investigations. As a basis for understanding this concept, and toaddress the content in this grade, students should develop their own questions andperform investigations. Students:1. Give examples of different ways scientists investigate natural phenomena and identifyprocesses all scientists use, such as collection of relevant evidence, the use of reasoning,the development and testing of hypotheses, and the use and construction of theory inorder to make sense of the evidence.2. Plan and conduct simple investigations based on student-developed questions thatpertain to the content under study, and write instructions others can follow in carrying outthe investigations.3. Identify dependent and independent variables in those investigations that havecontrols. And, if no controls are used, explain why.4. Recognize and explain that hypotheses are valuable even if they turn out not to be true,but that many investigations are not hypothesis driven.5. Write a report of an investigation that includes the problem to be solved, the methodsemployed, the tests conducted, the data collected or evidence examined, and theconclusions drawn.6. Locate information in reference books, back issues of newspapers and magazines, CD-ROMs, and online databases.7. Draw conclusions based on scientific evidence, and indicate whether furtherinformation is needed to support a specific conclusion or to discriminate among severalpossible conclusions.8. Record and organize information in simple tables and graphs, and identifyrelationships they reveal. Use tables and graphs as examples of evidence for explanationswhen writing essays or writing about lab work, fieldwork, etc. Read simple tables andgraphs produced by others, and describe in words what they show.9. Read a topographic map and a geologic map for evidence provided on the maps.10. Construct and interpret a simple map.


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Science and Technology6.2. Broad Concept: Although each of the human enterprises of science and technologyhas a character and history of its own, each is dependent on and reinforces the other.Students:1. Explain that computers have become valuable in science because they speed up andextend people’s ability to collect, store, compile, and analyze data, prepare researchreports, and share data and ideas with investigators all over the world.2. Explain that technology is essential to science for such purposes as measurement, datacollection, graphing and storage,computation, communication of information, and access to outer space and other remotelocations.

Solar System6.3. Broad Concept: Astronomy and planetary exploration reveal the structure and scaleof the solar system. As a basis for understanding this concept, students:1. Recognize that the solar system consists of the Earth, moon, sun, eight generallyrecognized other planets that orbit the sun and their satellites, and smaller objects, such asasteroids and comets.2. Describe how the planets move around the sun in elliptical orbits; and the near-coplanarity of the orbits, along with the principle of conservation of momentum, isevidence essential to our understanding of how the solar system was originallyformed.3. Explain that the moon is Earth’s only natural satellite, but several of the other planetshave natural satellites as well. Understand Earth also has many artificial satellites and thatall of these satellites, artificial and natural, are in elliptical orbits around their primaries.4. Explain that large numbers of chunks of rock and ices (asteroids and comets), muchsmaller than planets, orbit the sun.5. Describe, as seen from Earth, how planets change their position relative to thebackground of stars.6. Construct models or drawings to explain that the seasons are caused by the tilt of theEarth’s axis relative to the plane of its orbit and its revolution around the sun. Explainhow this results in uneven heating of the various parts of Earth’s surface thatvaries over the course of the year.7. Describe that as spring turns to summer at a particular place on Earth, the days growlonger and the sun moves higher in the sky, resulting in more intense heating. In fall andwinter, the opposite occurs. Explain how this variation in heating results in the seasons.8. Recognize and describe that the sun as a medium-sized star located near the edge of adisk-shaped galaxy of stars called the Milky Way, and that the universe contains manybillions of galaxies, and each galaxy contains many billions of stars.9. Recognize that the sun-Earth distance is such that it takes about eight minutes for lightfrom the sun to reach Earth. Know that the next nearest star is many thousands of timesfarther from Earth, and its light takes about four years to reach Earth.10. Explain that gravity is a force of attraction that every mass in the universe exerts onevery other mass, and everything on or anywhere near Earth is pulled toward Earth’scenter by a gravitational force.


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Solar System (Continued)11. Describe that the sun’s gravitational attraction holds Earth and the other planets intheir orbits, just as the planets’ gravitational attraction keeps their moons in orbit aroundthem.

Heat (Thermal Energy)6.4. Broad Concept: The transfer of energy through radiation and convection currentsaffects many phenomena on the Earth’s surface. As a basis for understanding thisconcept, students:1. Explain the meaning of radiation, convection, and conduction (three mechanisms bywhich heat is transferred to, through, and out of the Earth’s system).2. Describe that the heat from the sun falls on Earth unevenly because of its sphericalshape. Describe that regions close to the equator receive more concentrated solar energythan those closer to the poles.3. Observe and explain how uneven heating sets up convective cells in the atmosphereand oceans that distribute heat away from the equator.4. Explain that much of the heat from the sun is absorbed by the land and oceans and thenis released into the atmosphere.5. Recognize that, compared to other substances such as rock and soil, a given mass ofwater requires a greater input or output of heat energy to change its temperature by agiven amount.6. Describe why ocean temperatures, therefore, tend to vary seasonally less than landareas and coastal areas tend to have cooler summers and warmer winters than inlandareas at a similar distance from the poles.

Weather and Climate6.5. Broad Concept: Weather (in the short run) and climate (in the long run) involve thetransfer of energy in and out of the atmosphere. As a basis for understanding this concept,students:1. Explain how different regions receive different amounts of solar heating because oftheir latitude, clouds, surface water ice, and other variables. Understand that this resultsin large-scale convective air flow and weather patterns.2. Recognize and describe that the currents in the air and ocean distribute heat energy.3. Explain that a great deal of heat energy is absorbed when water evaporates and isreleased when it condenses. Illustrate that this cycling of water and heat in and out of theatmosphere plays a critical role in climatic patterns.4. Explain how mountain ranges and other major geographical features affect the climate(e.g., mountains produce rain shadows, land masses interrupt ocean currents).5. Describe how climates may have changed abruptly in the past as a result of changes inEarth’s crust, such as gas and dust from volcanic eruptions or impacts of meteorites,asteroids, and comets from space.6. Describe how the Earth’s atmosphere exerts a pressure that decreases with distanceabove sea level, and at every point is the same in all directions.


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Resources6.6. Broad Concept: Sources of materials differ in amounts, distribution, usefulness, andthe time required for their formation. As a basis for understanding this concept, students:1. Explain that fresh water is limited in supply and uneven in distribution; describe why itis essential for life as we know it and also for most human activities, including industrialprocesses.2. Recognize that fresh water is a resource that can be depleted or polluted, making itunavailable or unsuitable for humans.3. Recognize that the Earth’s resources for humans, such as fresh water, air, arable soil,and trees, are finite.4. Explain that the atmosphere and the oceans have a limited capacity to absorb wastesand recycle materials naturally.5. Investigate and describe how pollutants can affect weather and the atmosphere.6. Explain that recycling, reuse and the development of substitutes can reduce the rate ofdepletion of many minerals.7. Describe that most rainwater that falls in Washington, D.C., will eventually drain intothe Chesapeake Bay.8. Explain the important role of the water cycle within a watershed.

Rock Cycle6.7. Broad Concept: Rock materials are continuously recycled in the rock cycle. As abasis for understanding this concept, students:1. Recognize minerals are naturally occurring crystalline solids with definite chemicalcompositions and identify common minerals using a key to their diagnostic properties.)2. Examine and recognize most rocks are made of one or more minerals.3. Describe how igneous rocks are formed when older rocks are melted and thenrecrystallized. Understand they may be cooled deep in the Earth or at or near the surfaceas part of volcanic systems.4. Explain how metamorphic rocks are formed when older rocks are heated (short ofmelting) and/or subjected to increased pressure.5. Describe how sedimentary rocks are formed when older rocks are subjected toweathering into sediments, and those sediments are eroded, transported, deposited, thencompacted and cemented.6. Observe and describe common igneous, metamorphic, and sedimentary rocks,including granite, obsidian, pumice (igneous), slate, schist, marble (metamorphic),sandstone, shale, and limestone (sedimentary).


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Plate Tectonics6.8. Broad Concept: Plate tectonics explain important features of the Earth’s surface andmajor geologic events. As the basis for understanding this concept, students:1. Describe the solid lithosphere of Earth, including both the continents and the oceanbasins, and how it is broken into several plates that ride on a denser, hot, and graduallydeformable layer in the mantle called the asthenosphere (weak sphere).2. Explain why the Earth has a hot interior.3. Explain how lithosphere plates move very slowly, pressing against one another insome places, pulling apart in other places, and sliding past one another in others.4. Compare and contrast oceanic plates and continental plates.5. Explain the process in which plates push against one another, one of them may bedense enough to sink under the other, a process called subduction. Explain that oceaniclithosphere may sink under continental or oceanic lithosphere, but continental lithospheredoes not subduct.6. Describe that subducting plates may partially melt and form magma, which rises to thesurface as lava to feed volcanoes at the and form volcanic mountain chains associatedwith deep-sea trenches.7. Explain when plates push against each other and neither is dense enough to subduct(both continental), the plates will crumple and fold and form large mountain chains.8. Explain that earthquakes are sudden motions along breaks in the crust called faults, andvolcanoes/fissures are locations where magma reaches the surface as lava.9. Describe how earthquakes and volcanoes often, but not always, occur along theboundaries between plates.10. Describe that under the ocean basins, molten rock may well up between separatingplates to create new ocean floor.11. Explain how volcanic activity along the ocean floor may form undersea mountains,which can grow above the ocean’s surface to become islands (e.g., the Hawaiian Islands).12. Explain how physical evidence, such as fossils and surface features of glaciation,supports detailed explanations of how Earth’s surface has evolved over geologic time.


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Earth and Life History6.9. Broad Concept: Evidence from rocks allows us to understand the evolution of life onEarth. As the basis for understanding this concept, students:1. Explain how the Earth’s surface is built up and broken down by natural processes,including deposition of sediments, rock formation, erosion, and weathering.2. Describe that the history of life on Earth has been disrupted by major catastrophicevents, such as major volcanic eruptions or the impact of asteroids.3. Explain that although weathered rock is the basic component of soil, the compositionand texture of soil and its fertility and resistance to erosion are greatly influenced by plantroots and debris, bacteria, fungi, worms, insects, and other organisms.4. Explain how thousands of layers of rock confirm the long history of the changingsurface of Earth.5. Illustrate and describe that remains of changing life forms are found in successivelayers, although the youngest layers are not always found on top because of the folding,breaking, and uplifting of layers.6. Recognize that evidence from geologic layers and radioactive dating indicates thatEarth is approximately 4.6 billion years old and life on this planet has existed for morethan 3 billion years.7. Observe and explain that fossils provide evidence of how life and environmentalconditions have changed.

DOC 7 9/2006

2006CC2

district of columbia public schools science standards, grade 6 · unit 1 earth’s surface ......

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