Why is there sand at the beach?

Why is there sand at the beach?

Lesson narration:
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DISCUSS (1 of 2):

Why do you think the sand is purple?

DISCUSS (2 of 2):

Imagine you were at Pfeiffer Beach. How could you look for clues to help you solve the mystery of where the purple sand comes from?

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DISCUSS:

Can you think of a way tiny pieces of these rocks could move from the mountains all the way to the beach?

Hint...

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DISCUSS: What do you think would happen if the rocks in the river crashed into each other? Could this explain how there’s sand at the beach?

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Anchor Connection
Discuss. Look at the "Wonder" column of your class See-Think-Wonder chart.
Have any questions been answered by the past lesson?
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Step
01/09
You won't need your Strange River sheet for this Anchor Connection. Think-Pair-Share. How can rocks change the color of beaches?
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02/09
You saw how rocks can change the color of beaches. Discuss. Do you have any ideas about what might be changing the color of these rivers?
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Step
03/09
You know that the sources of the rivers are near mountains. Let’s see what the water at each source actually looks like in real life!
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Step
04/09
Here is where the rivers come together.
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05/09
This is what the Missouri River looks like near its source. Compare the color of the Missouri River in both pictures. What do you notice? Has the color changed much?
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06/09
This is what the Strange River looks like near its source. Compare the color of the Strange River in both pictures. What do you notice? Has the color changed much?
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07/09
The Strange River changes color from blue to light brown. Remember this as you look at the next slide!
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08/09
Study these two drawings. In one, the Strange River is brown at the source. In the other, it changes color farther down. Which is correct? Why do you think that?
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Step
09/09
Something must be changing the color of the Strange River here. Think-pair-share, but don’t update your worksheet! What do you think is changing the color of the river?
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ocean


1 of 15

a large area of salt water that covers the Earth
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beach


2 of 15

land next to a large area of water, often covered in sand
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microscope


3 of 15

a tool used to see very tiny things up close
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sand


4 of 15

very tiny pieces of rock, such as what you often see on the ground at a beach
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pebble


5 of 15

a small rock, usually with smooth edges
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rock


6 of 15

a solid natural material that is found on and under the surface of the Earth
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boulder


7 of 15

a large rock
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mountain


8 of 15

a high area of land with steep sides
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slope


9 of 15

where one side is higher than the other
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steep


10 of 15

something that is very high up on one end and very low at the other end
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river


11 of 15

a long, thin area of water that flows
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flow


12 of 15

to move along
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erosion


13 of 15

when tiny bits of rock are moved from one place to another
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downstream


14 of 15

toward the direction that water in a river or stream flows
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model


15 of 15

a pretend version of something that scientists use when the real thing is too big, small, or complicated to work with
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Image & Video Credits

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Exploration
kids at the beach by Image used under license from Shutterstock.com: bikeriderlondon
white sand beach by Image used under license from Shutterstock.com: Rob Marmion
girl on the beach by Image used under license from Shutterstock.com: ori-artiste
sand castle by Image used under license from Shutterstock.com: Kris Wiktor
Southwick Beach State Park by Easchiff
hand in sand by Image used under license from Shutterstock.com: kasidit
kid at Pfieffer Beach by The Offshore Aquaholic
purple sand by The Offshore Aquaholic
purple sand beach by Carson
kid holding sand by Image used under license from Shutterstock.com: Albina Glisic
footprints on purple beach by Image used under license from Shutterstock.com: mhgstan
hand holding purple sand by Akos Kokai
magnifiying glass by Image used under license from Shutterstock.com: underworld
close up of sand by Image used under license from Shutterstock.com: Mr Twister
zoomed view of sand by Image used under license from Shutterstock.com: AlexussK
green sand beach by Image used under license from Shutterstock.com: Alexander Demyanenko
close up of green sand by Brian W. Schaller
cliffs facing the beach by Image used under license from Shutterstock.com: Noradoa
close up of cliff by Image used under license from Shutterstock.com: jennyt
scuba diver by Image used under license from Shutterstock.com: Rostislav Ageev
Lepidolite (purple rock) by Spirit Rock Shop
purple mountains by Gonzo fan2007
falling rocks sign by Image used under license from Shutterstock.com: Michael Leslie
rock crashing down mountain by Joraj Dason
beach flooding by Muhammad Moolla
fast flowing river by Hayk Arakelyan
rocks flowing down river by Internet Geography
big blue waves by Image used under license from Shutterstock.com: bus109
chair and beach umbrella by Image used under license from Shutterstock.com: Aleks Melnik
clouds by Image used under license from Shutterstock.com: nikiteev_konstantin
mountains sillhouette by Image used under license from Shutterstock.com: Alex Ghidan
ocean concept by Image used under license from Shutterstock.com: Nikita Konashenkov
sand texture by Image used under license from Shutterstock.com: Ursa Major
Rainbow Beach by Cassarazzi
green rock by Image used under license from Shutterstock.com: Helen Cingisiz
hornocal by Lahi
close up of rainbow beach by cordyceps
stream on the beach by Humphrey Bolton
Activity
rushing river in Smoky Mountains by GreatSmokyMountains (© GSMA 2010. All rights reserved.)
turtles by Image used under license from Shutterstock.com: Dmitri Ma
rushing river by fccysf
Lesson narration:

Activity Prep

Print Prep

In this lesson, students investigate the effects of rocks tumbling in a river. Based on their observations, they construct an explanation for why there is sand at a beach. In the activity, Rocking the River, students pretend to be a river and tear up pieces of construction paper to model what happens to rocks as they travel along the river.

Preview activity

Exploration

22 mins

Wrap-Up

3 mins

Extend this lesson

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