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¿Por qué hay arena en la playa?
Work of Water Unit | Lesson 2 of 5

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¿Por qué hay arena en la playa?

Work of Water Unit | Lesson 2 of 5
Lesson narration:
English Spanish
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CONVERSEMOS (1 de 2): ¿Por qué crees que la arena es morada?

CONVERSEMOS (2 de 2): Imagínate que estás en la Playa Pfeiffer. ¿En dónde te fijarías para encontrar pistas que te ayuden a averiguar de dónde viene la arena morada?

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CONVERSEMOS:

¿Se te ocurre alguna manera que los pedacitos de las piedras podrías moverse de las montañas hasta la playa?

Pista...

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CONVERSEMOS: ¿Qué crees que sucede cuando piedras en el río chocan unas contra otras? ¿Podría esto explicar por qué hay arena en la playa?

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Paso
01/11
Si estás en una clase, forma un grupo de cuatro. Juntos, serán un río.
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Paso
02/11
Obtén tus materiales.
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Paso
03/11
Fíjate en el número en la parte de arriba de cada página.
Pon las páginas en orden del uno al cinco.
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Paso
04/11
Pon todas tus rocas en la parte de arriba de la montaña.
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Paso
05/11
Cuando comience el cronómetro, todos agarrarán una roca,
la romperán a la mitad y mandarán las mitades río abajo.
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Paso
06/11
Agarra los pedazos de piedra, rómpelos a la mitad, y deja que
se los lleve la corriente.
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Paso
07/11
Rompe esas piedras a la mitad y mándalas río abajo.
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Paso
08/11
Rompe cada piedra a la mitad y manda las piedras a la playa.
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Paso
09/11
En la playa, las olas chocan y rompen las piedras aún más.
Si puedes hacerlas más pequeñas, ahora es el momento de hacerlo.
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Paso
10/11
Agarra una hoja que dice «Dibuja las piedras en el río» y
dibuja las piedras.
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Paso
11/11
Conversemos:
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Slide Image
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océano


1 de 15

un área grande de agua salada en la Tierra
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playa


2 de 15

área de tierra cerca de una masa de agua grande, por lo regular cubierta de arena
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microscopio


3 de 15

una herramienta usada para ver cosas muy pequeñas de cerca
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arena


4 de 15

pedacitos muy pequeños de roca, por ejemplo, los que se ven en la playa
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piedrita


5 de 15

una roca pequeña, por lo regular con orillas lisas
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roca (o piedra)


6 de 15

un material natural y sólido que se encuentra en la superficie de la Tierra
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roca


7 de 15

una piedra grande
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montaña


8 de 15

un área de tierra elevada con lados empinados
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pendiente


9 de 15

cuando una parte está más elevada que otra
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empinado


10 de 15

algo que está muy alto en un lado y muy bajo en el otro
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río


11 de 15

un área larga y delgada de agua corriente

fluir


12 de 15

cuando algo se mueve fácilmente de un lugar a otro
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erosión


13 de 15

el movimiento de pedacitos de piedra de un lugar a otro
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río abajo


14 de 15

hacia la dirección en la que fluye el agua de un río o riachuelo
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modelo


15 de 15

una versión de mentiras de algo que los científicos usan cuando la cosa de verdad es algo demasiado grande, pequeño, o complicado para poder usarlo en sus estudios
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Mystery Science respects the intellectual property rights of the owners of visual assets. We make every effort to use images and videos under appropriate licenses from the owner or by reaching out to the owner to get explicit permission. If you are the owner of a visual and believe we are using it without permission, please contact us—we will reply promptly and make things right.

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
Credits

Featured Reviews

“The best part was after learning the process of rocks to sand we read Everybody Needs a rock (one of the suggested optional extras) and went rock hunting. It was such a fun activity. My second graders were so engaged and talked about how the small rocks we were finding used to be part of huge boulders. Fun!”
· Libba · Teacher
“The wrap-up, following the activity. The visual process of the bolder breaking down over & over really provided a great picture of erosion and the purple sand was a great way to get students hooked at the beginning. We added a wonder wall where students placed curiosities & questions throughout the video, so we could go back & answer any questions at the end of the unit. Their illustrations & summarizations were totally on point.”
· Diana · Teacher
“The best part was that Mystery Science showed a magnified view of sand. This introduced students to the fact that grains of sand can be many different colors and can come from many different kinds of larger rocks. My 2nd grade science classes used magnifying lenses to make enlarged drawings of individual grains of sand. ”
· · Teacher
“This lesson allowed for every single student to be fully engaged! They passed the ripped pieces of paper to each other and placed them on the paper quickly and excitedly and then FROZE when the visual timer went off! Having the timer included in the lesson was a big help, so I didn't have to use my phone and they could see it!! They have been talking about this lesson for weeks!”
· Bethany · Teacher
“The kids really enjoyed it. It was also easy to get the supplies ready for the activity and it was meaningful to the students. ”
· Kelly · Teacher
“We LOVED this one. The hands-on component with the rain showers and decreasing boulders was such fun for the kids, and an easy demonstration of how sand is formed. Thanks!”
· Linda · Homeschooler
“My students loved this experiment,and they really understood how sand got to the beach and about the color!”
· Cheryl · Teacher
“The short videos were perfect to engage the students and get them talking. They were so excited to learn more about how large boulders became sand. Every student ws engaged!”
· Nina · Teacher
“The students were so engaged. They got the concept since they could actually see the process. Great lesson. ”
· Loretta · Teacher
“The kids loved the hands-on activity. The visual that was built, really helped them to see the process of the boulder being broken down over time. The videoed timers, along with the water sounds, helped too. Very well done presentation. ”
· Jo-Anne · Teacher
“Learning about the purple sand. The activity was engaging and purposeful. The videos were helpful reinforcements of the activity. The students enjoyed learning about the different landforms around the world. The lesson helped the students gain a better understanding of weathering, erosion, and depositioning.”
· Katrina · Teacher
“The lesson was awesome as always! This is the first time in my career that I have felt like a good science teacher.”
· Tracy · Teacher
“They got it! :) YAY!! The way erosion is explained is perfect! The activity was simple and fun but more importantly they understand the concept now. Why is the sand purple? They were thinking pollution. Now they understand that sand is the color of rocks that have been eroded away. YAY! I couldn't be happier with this product! :) Thank you!”
· Joy · Teacher
“Students really enjoyed this lesson. Steps were easy to follow and material easily accessible. Prep time was quick. All level of EL's engaged.”
· Virginia · Teacher
“The children loved the hands on rock erosion activity. It really helped them understand how sand is created.”
· Janae · Teacher
“The students were able to retell and TEACH others about how sand is formed. They also made connections to yesterday's lesson about how rivers are different from other bodies of water because they travel all the way to the ocean. I had an administrator come in for a walkthrough while teaching this lesson and he was so impressed that the students were able to tell him every single part of how sand is formed! They were also able to answer his questions.”
· · Teacher
“The students really understood the process of why there is sand at the beach. The activity of "breaking up the rocks" as you go downstream was really effective. Thanks!”
· Joe · Teacher
“Great! Experiment was very engaging and easy to prepare! Can't wait to do this again next year!”
· Jill · Teacher
“A substitute teacher was here this day. She said that the lesson was very easy to understand and follow and the students were highly engaged. ”
· Heather · Teacher
“The students had many of the ideas and suggestions that where disproved in the video. It made the scenario very "real" to them. A couple made correct predictions so they were feeling very confident!”
· Patsy · Teacher
“I didn't think erosion could be fun for my students. They had a blast tearing up paper and really seemed to understand the concept.”
· Suzanne · Teacher
“Great video and hands-on activity that connected and could easily be referred to thoughout the lesson. Good visuals and language for bilingual/ESL students.”
· Janelle · Teacher
“The videos and the river activity! The students loved it and learned so much about beaches and where they come from.”
· Doreen · Teacher
“Getting to hear why my students thought the sand was purple. They were very creative coming up with answers, but then really did understand why it was purple at the end of the lesson. ”
· Margaux · Teacher
“The visual activities teach the concept so well! And we love the step by step instructions! THANK YOU!”
· Beth · Teacher
“This is a fantastic lesson! The kids had some misconceptions before we began this lesson. The kids now have a great understanding and will remember this well because of the fun activities!”
· Lisa · Teacher
“I love how the explorations stop to ask students to think critically! My second graders were engaged throughout the exploration and came up with some thoughtful explanations! Wonderful job!”
· Karen · Teacher
“Ripping the paper really helped kids see/experience how the rocks change to sand. I love the videos - the timer and directions are built in. Such easy planning and prep for the teacher. ”
· Reene · Teacher
Lesson narration:
English Spanish

Grade 2

Erosion & Earth’s Surface

Rocks, Sand, & Erosion

2-ESS2-2

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

I have a Mystery Pack

Draw the River Rocks worksheet 30 copies
River (5 sheets) printout Print 8 copies
Colored Construction Paper
24 sheets
Prep Instructions

We suggest students work in groups of four. Homeschool students can work alone.

Prepare “Paper Boulders”

Cut or tear each sheet of construction paper into about 12 pieces. We used a paper cutter to cut many sheets at the same time, making irregularly shaped pieces, but tearing or cutting with scissors will also work.

randomly cut paper

Each group (or single homeschool student) should start with 3 sheets worth of boulders (about 36). We recommend providing plenty of boulders at the beginning so that the students will still have large boulders at the end of the activity. That way, students will be able to see how the sizes of the rocks change as they move downstream.

Exploration

22 mins

Hands-On Activity

30 mins

Wrap-Up

3 mins

Grade 2

Erosion & Earth’s Surface

Rocks, Sand, & Erosion

2-ESS2-2

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Credits
 
Water Lesson 2: Why is there sand at the beach?

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