Big Idea: Big Idea: Water is Water is responsible for shaping and responsible for shaping and

reshaping landforms on Earth. reshaping landforms on Earth. Clean and adequate water Clean and adequate water sources are essential for sources are essential for

sustaining human life and sustaining human life and healthy ecosystems.healthy ecosystems.

VocabularyVocabulary Alluvial FanAlluvial Fan DrainageDrainage ErosionErosion MeanderMeander RiverbedRiverbed SedimentSediment ValleyValley

This is the Green River Valley in Colorado. It cuts deeply into the layers of rock and soil. The bank of the river is several hundred feet high.

This is the Sacramento River Valley in California. The banks of the river are just a few feet high. Frequent floods have made the surrounding farmland very fertile.

CompareCompare these 2 meandering rivers. these 2 meandering rivers.

In your opinion, what In your opinion, what claimsclaims can you can you make about why one river has cut so make about why one river has cut so deeply into the rock and soil, while the deeply into the rock and soil, while the other river has cut a very shallow other river has cut a very shallow basin?basin?

What What evidenceevidence from the picture from the picture supports your theory?supports your theory?

Modeling MaterialsModeling Materials

Diatomaceous earth tubsDiatomaceous earth tubs WaterWater Drip systemDrip system Wooden blocksWooden blocks ScrapersScrapers RulersRulers Time telling device – clock, timer, cell Time telling device – clock, timer, cell

phonephone

Focus QuestionFocus Question

Write a question you could test to Write a question you could test to find out which factor most greatly find out which factor most greatly influences the different shapes of the influences the different shapes of the two rivers.two rivers.

General Plan for ExperimentGeneral Plan for Experiment

What are we going to keep the same?What are we going to keep the same? (controls/constants)(controls/constants)

What are we going to change?What are we going to change?(independent variable)(independent variable)

What are we going to measure?What are we going to measure?(dependent variable)(dependent variable)

HypothesisHypothesis

Write a hypothesis about what you Write a hypothesis about what you think will happen if you change one think will happen if you change one river shaping factor.river shaping factor.

If______________, then_______________If______________, then_______________

because____________________________.because____________________________.

ProceduresProcedures

Explain the steps of your experiment.Explain the steps of your experiment. How will you test your question?How will you test your question?

First…First…

Second…Second…

Third…Third…

Next…Next…

Finally…Finally…

Data CollectionData Collection

How will you How will you collect the data?collect the data?

What will your What will your recorded data look recorded data look like?like?

0

10

20

30

40

50

60

70

80

90

1stQtr

2ndQtr

3rdQtr

4thQtr

East

West

North

0102030405060708090

100

1st Qtr 2nd Qtr 3rd Qtr 4th Qtr

ConclusionConclusionaka Making Meaning Meetingaka Making Meaning Meeting

Look back at your focus questionLook back at your focus question Conclusion should be the answer to the Conclusion should be the answer to the

focus questionfocus question

Write Around ConclusionWrite Around Conclusion– Each group member will get a sheet of paperEach group member will get a sheet of paper– For one minute the students will write their For one minute the students will write their

thoughts to answer the focus questionthoughts to answer the focus question– The paper then gets rotated through each The paper then gets rotated through each

group member, who adds to the statementgroup member, who adds to the statement

Future ExperimentsFuture Experiments

What other questions can you test What other questions can you test using the River Cutter model?using the River Cutter model?– What happens if you build levees to What happens if you build levees to

control floods?control floods?– How will plants affect erosion?How will plants affect erosion?– How do river meanders change over How do river meanders change over

time?time?– What happens to toxic waste in the soil?What happens to toxic waste in the soil?