GRADE LEVEL• 3-6

SUBJECT AREAS• EarthScience,Physical

Science,LifeScience

SKILLS• Organize,Analyze,Interpret,

Apply,Evaluate,Technology

VOCABULARYAbsorption,condensationconsumption,excretion,evaporation,deposition,flow,freezing,gravity,hydrogen,liquid,melting,molecule,oxygen,percolation,precipitation,respiration,solarenergy,solid,state,sublimation,transpiration,vapor

CONTENTSMeasurable Objectives

Background and Text Overview

Vocabulary

Activities

• TheWaterCycleActivityandAnswerKey

Take Action!

• PosterItems

• Activities

Assessments

• Pretest/PosttestandAnswerKey

• CriticalThinkingQuestions

• WhatDidILearn?OnlineQuizAnswerKey

Extensions

Resources

• ProjectWETResources

• AdditionalStudentResources

• AdditionalEducatorResources

MEASURABLE OBJECTIVESThelearnerwill:

• RecognizesolarenergyasthemaindriverforthemovementofwateronEarth.

• Describethemovementofwaterwithinthewatercycle.

• Identifythethreestatesofwaterandhowwatertransitionsbetweenthem.

BACKGROUND AND TEXT OVERVIEW

INTRODUCTIONTheWaterCycleistheendlessmovementofwateraroundtheplanet.Earth’snaturalsystemsareconstantlymovingandusingwater.Asaliquid,gasorsolid,poweredbythesunandtheforceofgravity,watertravelsover,underandabovethesur-faceoftheEarthinanincrediblejourneycalledthewatercycle.

OLD WATERDidyouknowtheworldhasthesameamountofwatertodayaswhentheEarthformedlongago?AccordingtoGeologists,Earthwasformedabout4.5billionyearsago.Volcanicerup-tionsreleasedvariousgasesandcreatedaprimitiveatmo-sphere—watervaporwasoneofthesegases.AstheearthcooledthevaporcondensedintoliquidandwaterraineddownontotheEarth’ssurfacecreatingtheoceanandseas.Nosignificantamountsofnewwaterhaveformedsincelongago,andthewaterformedthenhasnotdisappeared.TheEarth’sexistingwatermovesaroundtheplanetthroughacomplexwatercycle.Thewatercycleistheendlessmovementofwateraroundtheplanet.Waterchangesfromliquid,tosolidandvaporformasitmovesfromplacetoplaceontheEarth’ssurface,intheatmo-sphereandunderground.

The Water CycleWhere does water come from, and where does it go?

1 DiscoverWater.org©2011ProjectWETFoundation

WHAT DRIVES THE WATER CYCLE?Thesunprovidestheheaten-ergynecessarytocausewateronearthtochangestatesandmovethroughthewatercycle.Astem-peraturesincreaseicemeltsandliquidwaterevaporates.Whentemperaturesdecreasewatervaporcondensestoliquidformandliquidwaterfreezestosolid.

AnotherreasonwatermovesalongtheEarth’ssurfaceisgrav-ity.Waterflowsdownhill,fromhighertolowerelevationsduetotheforceofgravity.Gravitycausesriverstoflowandwatertoseepintotheground.Earth’snaturalsystemsareconstantlymovingandusingwater.Asaliquid,gasorsolid,poweredbythesunandtheforceofgravity,watertravelsover,underand

H2OWaterismadeofmillionsoftinymolecules—justlikeacookieappearstobeonesolidpiece,butwhencrumbled,itismadeupofmanytinypieces.Eachwatermolecule(smallestunitofwater)containstwohydrogen(H) atomsandoneatomofoxy-gen.Thesemoleculesconstantlymove.Heatmakesthemoleculesmovefasterandcoldmakesthemoleculesmoveslower.Themotionofmoleculesdeter-minesthestateofwater.Inthevaporstate,themoleculeshavealargeamountofheatenergy,moverapidlyandarespreadapart.Themoleculesinliquidwatermovemoreslowlyandareclosertogether.Asasolid(ice),themoleculescontaintheleastamountofenergy,sotheymoveveryslowly.

abovethesurfaceoftheEarthinanincrediblejourneycalledthewatercycle.

STATES OF WATERWaterexistsinthreeformsattheEarth’ssurface:liquid,solidandvapor.Liquidisthestateofwaterwithwhichwearemostfamil-iar.Thisistheformofwaterwedrink,andinwhichweswimandbathe.Watervaporisthegas-eousstateofwater.Watervaporisallaroundus,eventhoughwecan’tseeitmostofthetime.Waterinsolidformiscalledice.Waterchangesfromonestatetoanotherwhenheatenergyisaddedorlost.

Weallliveunderwater—justnotnecessarilyunderliquidwater.Thereiswatervaporintheairsurroundingusallthetime.

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STATES OF WATER

Watervaporcanturndirectlyintoasolid.Thisprocessiscalleddeposition.

Liquidwaterfreezesintoasolidwhencooled(liketheiceinyourfreezer).

Solidwatermeltsintoliquidformastemperaturesrise.

Whenwatervaporiscooled,itcondenses

intodropletsofliquid.

Liquidwaterevaporatesintoavaporwhenheated(thinkofthesteamyairinyourbathroomwhenyou

takeashower).

Solid watercanchangedirectly

intowater vapor.This

processiscalledsublimation.

DiscoverWater.org©2011ProjectWETFoundation

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ACTIVITIESTHE WATER CYCLE ACTIVITYPleaseseeThe Water Cyclestu-dentcopypage.

ANSWER KEYPleaseseestudent/teachercopypage.

TAKE ACTION! POSTER ITEMS1.Iwillwashthefamily’scarongrasssosoapdoesn’tenterthestormdrain.

2.Iwilloffertowatermyfam-ily’splantsorpetsforamonth.

ACTIVITIES• Hostawaterfestivalinyour

communityandaskstudentstohelpteachThe Incredible Journeytofestivalattendees.

• Visitthelocalwaterauthoritytofindoutmoreaboutwaterinthecommunity.Wheredoesmunicipalwatercomefrom?(Groundwater,wells,etc.)Whatarethelocalissuesasso-ciatedwiththewatersupply?Howwouldtheissuesaffectthewatercycle?

• Createaphoto-documentaryofthelocalwatershedthatrepresentseachaspectofthewatercycletoprintinthelocalnewspaperorpostonlinetoablogorvideosite.

ASSESSMENTSPRETEST/POSTTESTBeforestudentsvisitTheWaterCycleUnitoftheDiscover Water website,havethemtakethefollowingquiztoseewhattheyalreadyknowabouthowwatermovesaroundourplanet.Havestudentstakethesamequizagainasaposttesttomeasurelearning.

PleaseseeThe Water Cycle Pre-test/Postteststudentcopypage.

PRETEST/POSTTEST ANSWER KEY1. True

2. True

3. True

4. True

5. False

6. Thesun

7. True

CRITICAL THINKING QUESTIONSLEVEL 1Howdoeswatermove?

Depending on grade level and ex-pectations, answers could include discussion of flow, soaking in, percolation, consumption, excre-tion, transpiration, evaporation, precipitation and possibly deposi-tion and sublimation.

LEVEL 2Wheredoeswatercomefrom,andwheredoesitgo?

Answers should discuss the idea that all water on earth is recycled endlessly from place to place and state to state through the water cycle.

LEVEL 3Howdoesthesun,whichisover92millionmilesaway,drivethewatercycleonEarth?

Answers should include discussion of how solar energy heats water on Earth, causing it to change states from liquid to vapor.

WHAT DID I LEARN? ONLINE QUIZ ANSWER KEY

Q.Waterisneverusedup,butcyclesaroundtheplanet

continuously.

A. True

Q. Waterexistsinwhichofthefollowingstates:

A.Liquid,solidandvapor

Q.Whenwatermovesfromliquidforminalaketovaporformintheair,it:

A. Evaporates

Q. Thebiggestforcedrivingthewatercycleissolarenergyfromthesun.

A.True

Q.Gravitycauseswatertoflowovertheearth’ssurfaceandintotheground.

A.True

EXTENSIONS Ideasforwaystosupportandexpandlessonplansaboutthistopicorprovideadditionalac-tivitiesforadvancedlearners.

• Visitalocalwaterfeature(pond,lake,creek,beach—evenpuddle)andhavestu-dentswriteastoryaboutawaterdropletinthatlocation,discussinghowitgotthereandwhereitmightgonext.

• Havestudentsplacetheirowndishofwaterinsideoroutsideinthesunanddiscussorwriteaboutwhereitgoeswhenitevaporates.

• Useagroundwatermodeltodemonstratehowthewatercyclecontinuesunderground.

RESOURCESPROJECT WET RESOURCES

ProjectWETKIDS(KidsinDiscoverySeries)Booklets

DiscoverWater.org©2011ProjectWETFoundation

Hrennikoff,Margo.2006.“Imple-mentinganImaginativeUnit:WondersoftheWaterCycle.”Educational Perspectives,39(2),27-33.

McDuffie,Thomas.2007.“Pre-cipitationMatters.”Science and Children,44(9),38-42.

Robertson,WilliamC.2005.Air, Water, and Weather: Stop Faking It! Finally Understanding Science So You Can Teach It.Arlington,VA:NationalScienceTeacherAs-sociation.

Shepardson,DanielP.,BryanWee,MichellePriddy,LaurenSchellenberger,andJohnHarbor.2009.“WaterTransformationandStorageintheMountainsandattheCoast:MidwestStudents’Dis-connectedConceptionsoftheHydrologicCycle.”International Journal of Science Education,31(11),1447-1471.

Toft,JoanneandKathyScoggin.2007.“TheRippleEffect.”Science and Children,45(3),21-23.

Vowell,JulieandMariannePhillips.2007.“ADropthroughTime.”Science and Children,44(9),30-34.

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• Discover Ground Water and Springs

• Discover the Hudson River

• Discover the Waters of Nevada

• The Water Story

• Water, Every Drop Counts

ProjectWETActivities

• Adventures in Density

• Blue Planet

• Blue River

• Get the Ground Water Picture

• Just Passing Through

• Snow and Tell

• pringing Into Action

• Storm Water

• The Incredible Journey

• The Thunderstorm

• Urban Waters

• Your Hydrologic Bank Account

ADDITIONAL STUDENT RESOURCES

Cassino,Mark,andJonNelson.2009.The Story of Snow.SanFrancisco,CA:ChronicleBooks.

Hooper,Meredith.2008.A Drop in My Drink: A Story of Water on Our Planet.London,UK:FrancisLincolnChildren’sBooks.

Locker,Thomas.2002.Water Dance.SanDiego,CA:VoyagerBooks/Harcourt.

Rice,WilliamB.2010.Inside the Water Cycle.Minneapolis,MN:CompassPointBooks.

Waldman,Neil.2003.The Snow-flake: A Water Cycle Story.Minne-apolis,MN:MillbrookPress.

ADDITIONAL EDUCATOR RESOURCES

DiscoverWater.org©2011ProjectWETFoundation

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THE WATER CYCLE ACTIVITY Usethewordsbelowtocompletethecrosswordpuzzle.

ACROSS

1.Theprocessbywhichliquidwatermovesupwardsthroughaplantandevaporatesaswatervaporfromitsleaves.

5.Themovementofliquidwaterfromhighertolowerelevationduetogravity.

6.Theprocessbywhichwaterleavesananimalthroughwasteremoval.

8.Theprocessbywhichliquidwaterchangestowatervapor.

10.Theprocessbywhichwatervaporisexhaledandinhaledananimalbreathes.

11.Theprocessbywhichwatervaporchangestoliquidwater.

12.Theprocessbywhichsolidwater(ice)changesdirectlytowatervapor.

13.Theprocessbywhichliquidwateristakenupbytherootsofaplant.

DOWN

2. Themovementofliquidwaterthroughporespacesunderground.

3.Theprocessbywhichsolidwater(ice)changestoliquidwater.

4.Theprocessbywhichwatervaporchangesdirectlytosolidwater(ice).

5.Theprocessbywhichliquidwaterchangestosolidwater(ice).

7.Theprocessbywhichwaterentersananimalthrougheatinganddrinking.

9.WaterfallingasrainorsnowfromtheatmospheretoEarth.

EvaporationCondensationPrecipitation

MeltingFreezing

SublimationDepositionPercolation

FlowAbsorption

TranspirationRespiration

ConsumptionExcretion

StudentCopyPage

DiscoverWater.org©2011ProjectWETFoundation

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THE WATER CYCLE ACTIVITY (Answer Key)Usethewordsbelowtocompletethecrosswordpuzzle.

EvaporationCondensationPrecipitation

MeltingFreezing

SublimationDepositionPercolation

FlowAbsorption

TranspirationRespiration

ConsumptionExcretion

DiscoverWater.org©2011ProjectWETFoundation

AnswerKey

ACROSS

1.Theprocessbywhichliquidwatermovesupwardsthroughaplantandevaporatesaswatervaporfromitsleaves.

5.Themovementofliquidwaterfromhighertolowerelevationduetogravity.

6.Theprocessbywhichwaterleavesananimalthroughwasteremoval.

8.Theprocessbywhichliquidwaterchangestowatervapor.

10.Theprocessbywhichwatervaporisexhaledandinhaledananimalbreathes.

11.Theprocessbywhichwatervaporchangestoliquidwater.

12.Theprocessbywhichsolidwater(ice)changesdirectlytowatervapor.

13.Theprocessbywhichliquidwateristakenupbytherootsofaplant.

DOWN

2. Themovementofliquidwaterthroughporespacesunderground.

3.Theprocessbywhichsolidwater(ice)changestoliquidwater.

4.Theprocessbywhichwatervaporchangesdirectlytosolidwater(ice).

5.Theprocessbywhichliquidwaterchangestosolidwater(ice).

7.Theprocessbywhichwaterentersananimalthrougheatinganddrinking.

9.WaterfallingasrainorsnowfromtheatmospheretoEarth.

The Water Cycle Unit Pretest/Posttest1. Trueorfalse,nosignificantamountsofnewwaterhaveformedonearthformillionsofyears.

2. Trueorfalse,waterisconstantlymovingfromplacetoplacearoundtheplanet.

3. Trueorfalse,eachwatermoleculeismadeupoftwoHydrogenatomsandoneOxygenatom.

4. Trueorfalse,moleculesinwatervapormovefast.

5. Trueorfalse,moleculesinsolidwater(ice)movefast.

6. Themainsourceofenergydrivingthewatercycleis

a. Themoon

b. Gravity

c. Thesun

d. Wind

7. Trueorfalse,watercanchangedirectlyfromitssolidstatetovapor.

Score:___/7

StudentCopyPage

7 DiscoverWater.org©2011ProjectWETFoundation