Field Trips
- Grade Level:
- Lower Elementary: Pre-Kindergarten through Second Grade
- Subject:
- Science
- State Standards:
- Utah Science with Engineering Education Standards: Standard 2.1
Standard 2.1.1 Develop and use models illustrating the patterns of landforms and water on Earth.
Standard 2.1.2 Construct an explanation about changes in Earth’s surface that happen.
Essential Questions: How might landforms at Arches change?
Utah Science with Engineering Education Standards:
Standard 2.1: CHANGES IN THE EARTH’S SURFACE Earth has an ancient history of slow and gradual surface changes, punctuated with quick but powerful geologic events like volcanic eruptions, flooding, and earthquakes. Water and wind play a significant role in changing Earth’s surface. The effects of wind and water can cause both slow and quick changes to the surface of the Earth. Scientists and engineers design solutions to slow or prevent wind or water from changing the land.
Standard 2.1.1 Develop and use models illustrating the patterns of landforms and water on Earth.
Standard 2.1.2 Construct an explanation about changes in Earth’s surface that happen quickly or slowly. Emphasize the contrast between fast and slow changes.
Background
Earth’s surface comprises many features called landforms. Landforms are defined as a natural feature on the Earth’s surface. Landforms include mountains, valleys, canyons, mesas, buttes, spires, and many other features. They do not include things built by humans. Landforms can be found on both dry land and the ocean floor. Landforms are constantly changing. Faults and volcanoes on the Earth’s surface allow rock to be pushed up or pulled down, creating new landforms. Weathering and erosion then break down these landforms over time.
Most landforms at Arches are a product of weathering and erosion. Weathering refers to the group of destructive forces that break up rocks into smaller pieces near the Earth’s surface. Weathering can happen in several ways, but at Arches National Park, ice wedging is an important force. When water freezes, it expands, and this can break the rocks. Weathering helps break down a solid rock into smaller easily-eroded pieces.
Erosion is the picking up or physical removal of sediments by an agent, such as water or wind. When water in the form of rain lands on the earth’s surface, it flows downhill, eventually eroding away cliffs, canyons, and valleys. Erosion (along with weathering) slowly causes landforms like buttes and spires to get smaller. Sediments are the rocks, sand, and materials that are moved by erosion. It takes more energy to move sediments of large size and less energy to move smaller sized sediments.
Landform changes can happen quickly or slowly. Deep canyons, such as the ones carved by the Colorado River, can take millions of years to form. Wind, water, and glaciers slowly erode away mountain ranges, and the sediments from these mountains create new landforms elsewhere. Landforms can also change quickly. Volcanic eruptions, floods, landslides, rockfalls, and earthquakes can create new landforms or erode away landforms in a short period of time. Fast changes can be observed seasonally. As spring run-off enters streams and then drains away in the summer, sandbars, islands, and stream banks form and get washed away. Flash floods can also wash big pieces of rock into a stream and change the shape of the river in just a few hours. Volcanic eruptions create new land as lava erupting from the Earth cools into solid rock.
Most rocks in southeastern Utah are sedimentary, and the most common sedimentary rock is sandstone. Sandstone is made up of quartz sand grains cemented together by calcium carbonate or silica. The red appearance of many types of sandstone in the area is due to oxidized iron that coats the sand grains. Generally, sandstone erodes easily. Water is the most effective agent of erosion, but gravity and wind also play a part. The erosion of sandstone formed the unique canyons, needles, arches, natural bridges, spires, and balanced rocks of southeastern Utah.
Balanced Rock is a spire that stands a staggering 128 feet (39m) tall. While this formation may appear to be balancing, it’s not balanced at all. The slick rock boulder of Entrada Sandstone sits attached to its eroding pedestal of Dewey Bridge mudstone. The exposure of these two rock strata layers creates ideal conditions for the formation of arches and balanced rocks. Eventually, the 3,600 ton (over 4 million kg) boulder will come tumbling down as the erosional process continues to shape the landscape. Balanced Rock’s smaller sibling “Chip-Off-the-Old-Block” collapsed in the winter of 1975-76.
Because deserts produce fewer, smaller, and slower-growing vegetation than mountains, desert soils contain a low organic content. Biological soil crusts are extremely common in the southeastern Utah high desert and help to make up for this lack of organic matter. The soil crusts are a community of small organisms that form a living mat and secure the top few inches of sand particles against water and wind erosion. The crusts also increase absorption and retention of water and add nitrogen to the soil, an essential for plant growth. Biological soil crusts give desert soils a lumpy, spongy look, a result of gases produced by each living, breathing community member. Because of their incredible importance and extreme fragility, the preservation of biological soil crusts is the target of most of the educational efforts within the southeastern Utah national parks. To avoid walking on the crusts, hikers should walk on slickrock, on trails, or in washes. Don’t bust the crust!
PRE-TRIP ACTIVITY
Landforms Change?
Power point pictures of: Pictures of Balanced Rock, the Colorado river, a shallow desert stream, and a recent rock fall and landforms, backpack of items to bring for field trip; playdough.
Procedure
1) Show students a picture of Balanced Rock. Ask if students think Balanced Rock has always looked this way or if it has changed over time? Discuss their theories about how Balanced Rock came to look this way. Tell students that on their upcoming field trip they will visit Balanced Rock and explore the mystery of how the landscape at Arches changes over time. Their first clue to how Balanced Rock formed is that sometimes changes to the landscape happen too slow for us to see. Show a picture of the Colorado river, tell them that once upon a time, the canyon was as shallow as courthouse wash (or other example, show picture) The river digs away at this canyon a tiny bit every day and sand washes downstream very slowly. So slowly we usually don’t notice. It looks the same to us day in and day out. Sometimes change happens fast. Show a picture of the 2019 rockslide on the river road. Encourage students to discuss with their partners any patterns they notice in these two events? As a class, discuss how both events involve material breaking apart and washing away. (3-5 min)
2) Ask students if anyone has heard the word ‘landform’ before. Define a landform as a natural feature on the Earth’s surface. Ask students to think of an example and share it with the person next to them. Afterwards, have students share their examples with the group. Tell students sometimes landforms change quickly and sometimes the changes slowly. Show students pictures of various landforms and discuss how they might change over time. (5 min)
3) Give each student a piece of play dough. Have everyone in the class build a volcano. Ask a volunteer to describe how a volcano might change. Repeat having students build arches and, if time, a canyon. (15 min)
4) At the end, students should form their clay into a ball and collect them for use in the next class.
Landforms Change?
Objectives: Students will be able to:
a. Understand that the Earth’s surface is changing.
b. Name three landforms
Essential Question: Is the surface of the Earth changing?
Power point pictures of: Pictures of Balanced Rock, the Colorado river, a shallow desert stream, and a recent rock fall and landforms, backpack of items to bring for field trip; playdough.
Procedure
1) Show students a picture of Balanced Rock. Ask if students think Balanced Rock has always looked this way or if it has changed over time? Discuss their theories about how Balanced Rock came to look this way. Tell students that on their upcoming field trip they will visit Balanced Rock and explore the mystery of how the landscape at Arches changes over time. Their first clue to how Balanced Rock formed is that sometimes changes to the landscape happen too slow for us to see. Show a picture of the Colorado river, tell them that once upon a time, the canyon was as shallow as courthouse wash (or other example, show picture) The river digs away at this canyon a tiny bit every day and sand washes downstream very slowly. So slowly we usually don’t notice. It looks the same to us day in and day out. Sometimes change happens fast. Show a picture of the 2019 rockslide on the river road. Encourage students to discuss with their partners any patterns they notice in these two events? As a class, discuss how both events involve material breaking apart and washing away. (3-5 min)
2) Ask students if anyone has heard the word ‘landform’ before. Define a landform as a natural feature on the Earth’s surface. Ask students to think of an example and share it with the person next to them. Afterwards, have students share their examples with the group. Tell students sometimes landforms change quickly and sometimes the changes slowly. Show students pictures of various landforms and discuss how they might change over time. (5 min)
3) Give each student a piece of play dough. Have everyone in the class build a volcano. Ask a volunteer to describe how a volcano might change. Repeat having students build arches and, if time, a canyon. (15 min)
4) At the end, students should form their clay into a ball and collect them for use in the next class.
Landforms to discuss:
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Mountains - the highest thing around.
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Valleys - low land between mountains or cliffs.
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Canyon – a narrow valley with steep sides
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Plains - land that is mostly flat.
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Hills - Hills are smaller than mountains
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Volcanoes -mountains made when liquid rock rises to the surface of the Earth
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Oceans are large bodies of salt water.
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Lakes are small bodies of water surrounded by land.
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Butte – an isolated hill with steep sides and a small flat top
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Spire – a tall column of rock
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Rivers- a long body of water that flows through the land
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Islands- an area of land surrounded by water
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Cliffs- tall, steep rocks that are straight up and down like a wall
STATION #1
Erosion - How rivers carve canyons
PVC tube cut in half lengthwise, water jug, 4 bike-type squeeze bottles, strainer, bucket, pictures of Colorado River running clear and running brown, “River” and “Canyon” landform cards.
Procedure
1) Show students two pictures of the Colorado River and ask what they notice is different. Point out the color of the river differs between the two pictures. Tell students they will solve the mystery of why the Colorado River sometimes runs reddish brown, using a model of the Colorado River. Instruct students to pick up two palm-sized rocks on their walk over to the model. (2-3 min)
2) Show the students the PVC tube and explain the tube is a model of a river. Models are like the real thing, but this one is smaller. Discuss how this model differs from a real river. One end of the tube should be open and set slightly lower to pour into a bucket. Have students sprinkle their rocks and sand (optional: add sticks) in the tube. Invite students to predict what will happen when you pour (1) a little water, (2) a moderate amount of water, (3) a flash-flood amount of water. Pour water into the top of the tube. Ask them to pay close attention to how far their rocks and sand move. After each round, discuss how much and how things moved. Discuss how smaller and lighter items moved differently than larger and heavier items. Compare their results to what happened with other water amounts. Discuss how the model allows us to see the slow process of erosion. (5-7 min)
3) Ask if students have heard of or remember a flash flood. Encourage students to share their experiences. Lift the end of the tube so the water will move faster and repeat the process. Discuss the results. Remind students while erosion usually happens slowly, bit by bit, sometimes things happen fast. Lift the tube to a steep angle and demonstrate a “mega-flood” to clean out the tube (2-3 min)
4) Ask if the patterns they observed in their model might be observed in the real world. Once again, show pictures of the Colorado River when the water is green and when it’s really red. Have students compare and discuss why the Colorado River sometimes turns red. Ask if they think it is red right now, given the latest weather. (3-5 min)
5) Show the canyon formation foam model. Remind student how, in the Colorado River model, the water carried away rocks and sand and the canyon got deeper. The river can go through flat land, but the river picks up rocks and carries them downhill/downstream. Show how the river eventually carves the canyon even deeper. Explain that the river is a landform, and the canyon is a landform. Show landform cards for these terms. Without moving, have students look for a canyon visible at Arches. Ask if student know of other canyons (like Moonflower). (5-7 min)
6) Tell students erosion can move sand and rocks all the time, even where they are standing. Take students to the edge and ask them to predict where water will flow. Give them water to pour over the cliff. Have them watch as sand moves downhill. Ask them if erosion moves sand slowly or quickly. (3-5 min)
Misconception: some students don’t realize water and sediments always flow downhill.
Erosion - How rivers carve canyons
Objectives: Students will:
a. plan and carry out an investigation to demonstrate erosion
Essential Question: How does water move sand and rocks? How do canyons form?
MaterialsPVC tube cut in half lengthwise, water jug, 4 bike-type squeeze bottles, strainer, bucket, pictures of Colorado River running clear and running brown, “River” and “Canyon” landform cards.
Procedure
1) Show students two pictures of the Colorado River and ask what they notice is different. Point out the color of the river differs between the two pictures. Tell students they will solve the mystery of why the Colorado River sometimes runs reddish brown, using a model of the Colorado River. Instruct students to pick up two palm-sized rocks on their walk over to the model. (2-3 min)
2) Show the students the PVC tube and explain the tube is a model of a river. Models are like the real thing, but this one is smaller. Discuss how this model differs from a real river. One end of the tube should be open and set slightly lower to pour into a bucket. Have students sprinkle their rocks and sand (optional: add sticks) in the tube. Invite students to predict what will happen when you pour (1) a little water, (2) a moderate amount of water, (3) a flash-flood amount of water. Pour water into the top of the tube. Ask them to pay close attention to how far their rocks and sand move. After each round, discuss how much and how things moved. Discuss how smaller and lighter items moved differently than larger and heavier items. Compare their results to what happened with other water amounts. Discuss how the model allows us to see the slow process of erosion. (5-7 min)
3) Ask if students have heard of or remember a flash flood. Encourage students to share their experiences. Lift the end of the tube so the water will move faster and repeat the process. Discuss the results. Remind students while erosion usually happens slowly, bit by bit, sometimes things happen fast. Lift the tube to a steep angle and demonstrate a “mega-flood” to clean out the tube (2-3 min)
4) Ask if the patterns they observed in their model might be observed in the real world. Once again, show pictures of the Colorado River when the water is green and when it’s really red. Have students compare and discuss why the Colorado River sometimes turns red. Ask if they think it is red right now, given the latest weather. (3-5 min)
5) Show the canyon formation foam model. Remind student how, in the Colorado River model, the water carried away rocks and sand and the canyon got deeper. The river can go through flat land, but the river picks up rocks and carries them downhill/downstream. Show how the river eventually carves the canyon even deeper. Explain that the river is a landform, and the canyon is a landform. Show landform cards for these terms. Without moving, have students look for a canyon visible at Arches. Ask if student know of other canyons (like Moonflower). (5-7 min)
6) Tell students erosion can move sand and rocks all the time, even where they are standing. Take students to the edge and ask them to predict where water will flow. Give them water to pour over the cliff. Have them watch as sand moves downhill. Ask them if erosion moves sand slowly or quickly. (3-5 min)
Misconception: some students don’t realize water and sediments always flow downhill.
STATION #2
Changing Landforms
Hide the ingredient cards before the students arrive.
Procedure
1)Take students to an area where they can view the landscape. Discuss the things they see and point out patterns they observe. With a partner, have students discuss how the landscape might have looked in the past and what they predict the landscape will look like in the future. Ask the students to point out their favorite landforms and tell them many landforms they see at Arches were made with the same “recipe.” (3-5 min)
2) Bring students to an area to sit. Pull out the recipe card and pretend to be amazed that the ingredients are missing. “Find” the secret decoder and go on a treasure hunt to find the missing ingredients for making landforms. Discuss who will be in charge of collecting the first ingredient. Ask students to walk fast, but not to run. Read the first clue as a group. This will lead students to the water card. The lead student should collect the ingredient card, and place it on the Recipe Card. Have students read water together. Continue in the same manner, next finding gravity, then sandstone, and finally time. Demonstrate gravity by having students pick up a small rock and carefully dropping it. (5 min)
3) Tell students it is time to make landforms. Bring students to the sand pile and tell them the pile is a model of a hill or a mountain of sandstone at Arches. Squirt a little water on the pile and discuss the role of water, washing away sandstone pieces a little at a time. Ask the students which way the washed-away sand moves. Gravity is pulling the sand down and away from the pile. For the time ingredient, students should imagine the hill is real sandstone and think about how often it rains in the desert. Encourage a discussion about how much time and water would be needed to wash away landforms. Have students take turns pouring water on the model for the count of three and observe how the shape of the sand pile changes. Point out “cliffs” and “canyons” forming in the model. Explain that some sandstone is harder than others. Hard sandstone erodes more slowly than soft sandstone, making the unique formations throughout the area. After each turn, point out the landforms created by movement of sand and buried rocks. Discuss how both fast and slow changes affect what students observe. Remind the students that the model started off as a mesa, but now it has changed into other landforms. (5-7 min)
4) To help remember how landforms change at Arches. Teach and practice the Landform Recipe Rhyme: “Sandstone, water, gravity and time; that’s the landform recipe rhyme.” Teach hand motions to go with the rhyme: make a circle with your fist for “sandstone” make fish swimming motions for “water,” bringing hands down for “gravity”, and pointing to wrist for “time,” and marching in place with arms swinging (or snapping fingers) during “that’s the sandstone recipe rhyme.” Repeat this rhyme several times using different speeds and/or voices. (2-3 min)
5) Remind students that once sandstone is exposed to air, it starts to break apart and wash away. The science terms for these processes are erosion and weathering. Weathering is the wearing down of rocks and erosion is the washing away of the broken bits. As an example, ask the students if they have ever drawn with sidewalk chalk so much their chalk got smaller? Tell the students they were weathering their chalk, and when it washed away, that was erosion. Discuss real causes of erosion, such as wind, water, and ice. Remind students that wind and water can cause both slow and quick changes to the surface of the Earth. Ask them to name examples of each. (3-5 min)
6) Take a short hike on the sandstone, ask students to look for patterns in the rocks that might indicate weathering. Tell students that at Arches, ice is the number one cause of weathering.
7) Turn students into water droplets. Have everyone stand shoulder to shoulder in a circle. Tell the students they are water droplets during a nice, warm day. Explain that when the sun goes down, it gets really cold, and they are freezing. Have them stick out their elbows. Point out how the circle got bigger when the water molecules froze. Ask students if they’ve ever put a can of pop or a water bottle in the freezer and forgotten it. What happened? Explain that water expands when it freezes, making the cans or bottles explode. When water thaws, it gets smaller again. Everyone should stand shoulder to shoulder again. Go through the cycle of night and day, freezing and thawing, several times. Find a crack in the sandstone and discuss how water might get into the crack. Have students pretend to slither into a crack, visualize themselves freezing, and pushing apart the crack. Emphasize that in the real world, the process happens millions of times until eventually the rocks break apart slowly. This causes big, quick changes like rockfalls. Have students act out freezing and thawing until eventually rock falls away and they all fall down. (5 min)
8) Tell students they are going to put all this together to make another model to demonstrate how Arches form. Show the students how to make a sandstone fin in damp sand. Scrape the sides at the fin’s base until an arch forms. Keep scraping until the arch collapses and discuss which ingredient made the arch collapse. Discuss how this process contained both fast and slow changes. Allow students to find a spot in the sand to build their own fins and arches. Bring the squirt bottle around and ask if the students need any water to create new landforms or collapse their arch. Let students rebuild the fins and arches until it’s time to switch stations. (5 min)
Misconception: Younger students often think rock formations grew up rather than being left behind when things around them erode away. Using the model, point out how the water washes sand away, leaving spires, cliffs, and if possible, balanced rocks.
Changing Landforms
Objectives: Students will be able to:
a. Name two ways that landforms change.
b. Describe that formations look the way they do because rocks and sand were taken away
Essential Question: How do landforms change over time?
Materialssecret decoder; clues; recipe card; ingredient cards (water, gravity, sandstone, time); bike-type squirt bottle; extra water.
NoteHide the ingredient cards before the students arrive.
Procedure
1)Take students to an area where they can view the landscape. Discuss the things they see and point out patterns they observe. With a partner, have students discuss how the landscape might have looked in the past and what they predict the landscape will look like in the future. Ask the students to point out their favorite landforms and tell them many landforms they see at Arches were made with the same “recipe.” (3-5 min)
2) Bring students to an area to sit. Pull out the recipe card and pretend to be amazed that the ingredients are missing. “Find” the secret decoder and go on a treasure hunt to find the missing ingredients for making landforms. Discuss who will be in charge of collecting the first ingredient. Ask students to walk fast, but not to run. Read the first clue as a group. This will lead students to the water card. The lead student should collect the ingredient card, and place it on the Recipe Card. Have students read water together. Continue in the same manner, next finding gravity, then sandstone, and finally time. Demonstrate gravity by having students pick up a small rock and carefully dropping it. (5 min)
3) Tell students it is time to make landforms. Bring students to the sand pile and tell them the pile is a model of a hill or a mountain of sandstone at Arches. Squirt a little water on the pile and discuss the role of water, washing away sandstone pieces a little at a time. Ask the students which way the washed-away sand moves. Gravity is pulling the sand down and away from the pile. For the time ingredient, students should imagine the hill is real sandstone and think about how often it rains in the desert. Encourage a discussion about how much time and water would be needed to wash away landforms. Have students take turns pouring water on the model for the count of three and observe how the shape of the sand pile changes. Point out “cliffs” and “canyons” forming in the model. Explain that some sandstone is harder than others. Hard sandstone erodes more slowly than soft sandstone, making the unique formations throughout the area. After each turn, point out the landforms created by movement of sand and buried rocks. Discuss how both fast and slow changes affect what students observe. Remind the students that the model started off as a mesa, but now it has changed into other landforms. (5-7 min)
4) To help remember how landforms change at Arches. Teach and practice the Landform Recipe Rhyme: “Sandstone, water, gravity and time; that’s the landform recipe rhyme.” Teach hand motions to go with the rhyme: make a circle with your fist for “sandstone” make fish swimming motions for “water,” bringing hands down for “gravity”, and pointing to wrist for “time,” and marching in place with arms swinging (or snapping fingers) during “that’s the sandstone recipe rhyme.” Repeat this rhyme several times using different speeds and/or voices. (2-3 min)
5) Remind students that once sandstone is exposed to air, it starts to break apart and wash away. The science terms for these processes are erosion and weathering. Weathering is the wearing down of rocks and erosion is the washing away of the broken bits. As an example, ask the students if they have ever drawn with sidewalk chalk so much their chalk got smaller? Tell the students they were weathering their chalk, and when it washed away, that was erosion. Discuss real causes of erosion, such as wind, water, and ice. Remind students that wind and water can cause both slow and quick changes to the surface of the Earth. Ask them to name examples of each. (3-5 min)
6) Take a short hike on the sandstone, ask students to look for patterns in the rocks that might indicate weathering. Tell students that at Arches, ice is the number one cause of weathering.
7) Turn students into water droplets. Have everyone stand shoulder to shoulder in a circle. Tell the students they are water droplets during a nice, warm day. Explain that when the sun goes down, it gets really cold, and they are freezing. Have them stick out their elbows. Point out how the circle got bigger when the water molecules froze. Ask students if they’ve ever put a can of pop or a water bottle in the freezer and forgotten it. What happened? Explain that water expands when it freezes, making the cans or bottles explode. When water thaws, it gets smaller again. Everyone should stand shoulder to shoulder again. Go through the cycle of night and day, freezing and thawing, several times. Find a crack in the sandstone and discuss how water might get into the crack. Have students pretend to slither into a crack, visualize themselves freezing, and pushing apart the crack. Emphasize that in the real world, the process happens millions of times until eventually the rocks break apart slowly. This causes big, quick changes like rockfalls. Have students act out freezing and thawing until eventually rock falls away and they all fall down. (5 min)
8) Tell students they are going to put all this together to make another model to demonstrate how Arches form. Show the students how to make a sandstone fin in damp sand. Scrape the sides at the fin’s base until an arch forms. Keep scraping until the arch collapses and discuss which ingredient made the arch collapse. Discuss how this process contained both fast and slow changes. Allow students to find a spot in the sand to build their own fins and arches. Bring the squirt bottle around and ask if the students need any water to create new landforms or collapse their arch. Let students rebuild the fins and arches until it’s time to switch stations. (5 min)
Misconception: Younger students often think rock formations grew up rather than being left behind when things around them erode away. Using the model, point out how the water washes sand away, leaving spires, cliffs, and if possible, balanced rocks.
STATION #3
Secrets in the Soil
crypto job flip book, large hand lenses, Crypto electron microscope pictures; cyanobacteria photos, crypto flannel board, flannel characters; flannel board story; crypto costume hats; crypto practice mats; 3-4 microscopes
Procedure
1) As you walk to the station, take students to several patches of crypto and have them take a mental picture of it. Discuss what they see besides rock. Ask them what happens when the sand blows. Why doesn’t it all blow away? If they have already been to the moving sediments station, discuss how sand can move. Tell student their other stations are about how erosion creates landforms. At this station, they will discover something that prevents erosion. Living communities called biological soil crusts help slow erosion and weathering. Point out other organisms in the crust. (2-3 min)
2) Using the flannel board to tell the story of CB the crypto. Make this story interactive and dramatic. (5-7 min)
3) Review how soil crusts help the desert by reading the flipbook as a group. Refer to the story as you discuss how the crust holds the soil in place, preventing erosion; soaks up and holds water like a sponge, provides nutrients or fertilizer for plants, and provides protected places for seeds to grow. Remind students of the kids that stepped on the soil crust in the story, and how devastating being crushed was to CB. Compare the growth of crypto to human growth rates. Ask if relatives students haven’t seen for a while ever comment on how much they have grown? This never happens to CB. While CB grows slowly, his clumps can break apart in just a few seconds. Ask the students if it would be better to wait for soil crust to regrow, or train people not to step on them. (3-5 min)
4) Discuss places people can walk without stepping on soil crust. Show students the crypto mats as a model for patches of crypto, discuss how the path through may be a trail or a wash and let students take turns tiptoeing through the crypto obstacle course, avoiding the crypto patches. Allow students to move the patches closer together to make the model harder and try again. Take students on a walk through a tricky area where they can practice their new crust hopping skills. (2-3 min)
5) Have the students lay belly-down in front of a patch of crypto and challenge them to observe cryptos closely for 30 seconds without talking. Then, ask each student to name something they see in the soil crust. Discuss patterns students observe and speculate why they occur. Hand out hand lenses and ask the students to point to different things they see on the cryptos like: lichens, mosses, plants, an indentation to hold a seed, an insect, etc. referring to characters in the story. (3-5 min)
Secrets in the Soil
Objectives: Students will be able to:
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Explain two roles of biological soil crusts
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Name two places to walk to avoid stepping on soil crusts
Essential Question: What does black lumpy crust on the dirt do?
Materialscrypto job flip book, large hand lenses, Crypto electron microscope pictures; cyanobacteria photos, crypto flannel board, flannel characters; flannel board story; crypto costume hats; crypto practice mats; 3-4 microscopes
Procedure
1) As you walk to the station, take students to several patches of crypto and have them take a mental picture of it. Discuss what they see besides rock. Ask them what happens when the sand blows. Why doesn’t it all blow away? If they have already been to the moving sediments station, discuss how sand can move. Tell student their other stations are about how erosion creates landforms. At this station, they will discover something that prevents erosion. Living communities called biological soil crusts help slow erosion and weathering. Point out other organisms in the crust. (2-3 min)
2) Using the flannel board to tell the story of CB the crypto. Make this story interactive and dramatic. (5-7 min)
3) Review how soil crusts help the desert by reading the flipbook as a group. Refer to the story as you discuss how the crust holds the soil in place, preventing erosion; soaks up and holds water like a sponge, provides nutrients or fertilizer for plants, and provides protected places for seeds to grow. Remind students of the kids that stepped on the soil crust in the story, and how devastating being crushed was to CB. Compare the growth of crypto to human growth rates. Ask if relatives students haven’t seen for a while ever comment on how much they have grown? This never happens to CB. While CB grows slowly, his clumps can break apart in just a few seconds. Ask the students if it would be better to wait for soil crust to regrow, or train people not to step on them. (3-5 min)
4) Discuss places people can walk without stepping on soil crust. Show students the crypto mats as a model for patches of crypto, discuss how the path through may be a trail or a wash and let students take turns tiptoeing through the crypto obstacle course, avoiding the crypto patches. Allow students to move the patches closer together to make the model harder and try again. Take students on a walk through a tricky area where they can practice their new crust hopping skills. (2-3 min)
5) Have the students lay belly-down in front of a patch of crypto and challenge them to observe cryptos closely for 30 seconds without talking. Then, ask each student to name something they see in the soil crust. Discuss patterns students observe and speculate why they occur. Hand out hand lenses and ask the students to point to different things they see on the cryptos like: lichens, mosses, plants, an indentation to hold a seed, an insect, etc. referring to characters in the story. (3-5 min)
6) Show students the magnified photos of cyanobacteria, increasing magnification with each photo. Then takes students over to the microscopes and observe the sheaths. (3-5 min)
7) Go for a walk and search for soil crusts with cb’s different friends and different size clumps. Along the way, review the roles of biological soil crusts and the three best places to walk to avoid busting the crust.
Optional extension:
Tell students they are going to act out the formation of crypto. Give each student a crypto part hat. Give specific boundaries and tell the students they are going to play a game like tag. The student who is the cyanobacteria must use their long stringy gloves to tag each of the other students who are sand grains, lichen, and moss. The first student tagged will grab onto the cyanobacteria’s shoulders, forming a snake, and follow them as they try to get more parts. As tagged students join the clump, they grab the back of the snake until an entire crypto bump is made (all the students join). Remind students that since Crypto’s grow slowly, they must walk. If they go out of bounds, they must freeze for 30 seconds. If time after the first round, students can switch roles and play again. This time, as they play, the instructor can alter the game play by announcing changes in the environment (e.g. “Long Dry Summer” = line has to walk in slow motion; “wet year” = CB can speed walk; instructor says “Crusher” = the line breaks apart and cyanobacteria has to start all over) (5-10 min)
Misconception: Students may have heard soil crusts take hundreds or millions of years to grow back. After a disturbance, crusts start to grow back right away, but it takes many years for crusts to get their bumps, and decades for moss and lichens to colonize on crusts so nitrogen fixation can take place. The wetter and cooler an area and the softer the soil, the faster crusts will grow.
CB – Life of a crypto
Once upon a time there lived a tiny creature named CB, who lived in the sand of Arches National Park. CB was long and skinny with sticky skin; so sticky that as he grew, he stuck to the giant sand grain boulders surrounding him. After many years, he and all the boulders he surrounded made a huge clump of sand.
CB loved the rain. When rain filled all the cracks and crevices around him with water, CB would become soft and be able to stretch out and grab even more sand boulders, a very fun game. Unfortunately, the rain did not fall very often. Many times, he felt the searing heat of winter and the frigid cold of summer pass him by as he slowly gathered more sand grains into his clump.
Eventually, after numerous years, CB had grown enough to become a very large clump of sand, perhaps even as large as a pinecone. He grew so big, he realized he wasn’t the only clump of sand. All around him, other creatures just like him were gathering the sand and pulling it into clumps around themselves as well. As much as CB liked the rain, he also enjoyed the sunlight. He turned it into food so he would be able to grow when the rains came.
One day a tiny green speck blew into a crack on the top of CB’s clump. Each winter, when the ground froze, that crack became deeper and until it grew deep enough for this green speck to get stuck. The green speck liked the rains too and just like CB it grew a little with every storm. CB marveled at his new friend, who told him her name was Molly Moss. She was very fuzzy; and unlike CB, she reached for the sky as she grew, rather than digging into the ground. Together they whittled away the seasons, telling each other jokes and stories. Molly always made CB laugh by turning bright green whenever she got wet.
One day, another speck landed in a crack on the top of CB. This speck was dark black and made the most wonderful, tasty treat from the air. Her name was Lilly Lichen, and she told CB her treat was called nitrogen. She didn’t make it, she just pulled it from the air. There was so much she had plenty to share. Eventually she got her sister Lolly lichen to come live with them too. Lolly was gray.
The friends lived together for many years until one day they heard a strange noise. It was loud and scary. They all looked up: CB and Molly and Lilly and Lolly. There, way up in the air, were two giant two legged creatures, with bare legs and arms and big bags on their backs. They were laughing and pushing and shoving each other as they walked, making great roars of sound that rolled across the ground.
The two-leggeds were jumping from rock to rock, trying not to step on CB and his friends, but it was no use. One of the giants lost its footing and landed right on CB. Within seconds the foot disappeared, back on the rock, running after his friend down the rock, but so was half of CB’s clump. All the sand grain boulders he had gathered so painstakingly for so many years blew away in the wind, along with his friends Molly and Lilly and Lolly.
There was nothing he could do but wait for the rain. When the water fell, he worked hard stretching and grabbing boulders, growing his clump bit by bit. Many times, the winter and the spring came and eventually his clump got big again, so big that the top cracked in the freezing winter. The next spring, a small green speck landed in the crack.
“Hello,” she said, “I think you knew my mother. Her name was Molly Moss.”
From that day on, CB and the daughters of Molly and Lilly and Lolly lived happily ever after, grabbing boulders and waiting for the rain to come in the sand at Arches National Park.
STATION #4
Balanced Rock
Cards with multiple examples of landforms (butte and spire); Magic Window showing Balanced Rock; 3D foam model of Balanced Rock
Procedure
Balanced Rock
Objective: Students will be able to:
a. Identify buttes and spires
b. Describe the formation and changes of buttes and spires
Essential Question: How does a butte change into a spire? How might Balanced Rock change?
MaterialsCards with multiple examples of landforms (butte and spire); Magic Window showing Balanced Rock; 3D foam model of Balanced Rock
Procedure
1) Show a sandstone rock and ask students to pass it around and tell one thing they notice about the rock. Ask students if they can see sand coming off the rock and what in nature might also cause sand to come off the rock. Explain that all the rocks around them, including Balanced Rock, are made of sandstone. (2-3 min)
2) Have students focus on Balanced Rock. Ask students if they think Balanced Rock will change. Show students the model of Balanced Rock. Use the model to demonstrate and explain how a butte changes into a spire through weathering and erosion. Along the way, use landform cards to show the differences in specific stages of the story. Include how ice breaks rocks apart. Discuss how the model differs from the actual Balanced Rock. (7-10 min)
3) Allow students to speed up time and act out the formation of Balanced Rock. Go through the story of the formation of Balanced Rock again by playing a game. Have students form a line about 20 feet from the model. Play a round of red light/ green light. The first one to tap you on the back gets to pick the next piece to erode from the model. Making the appropriate land slide noises, “wash” away the chosen piece by placing the piece in a pile a few feet away. Once all the removable pieces are gone, hold the model up to balanced rock and discuss similarities and differences to the real thing. Have students reiterate how it formed. And ask what they think happens to all the rock bits that fell off? Ask again if they think Balanced Rock will stay the same or change over time. (7-10 mins)
4) Investigate what could happen to Balanced Rock by using clues from the past to figure out what might happen in the future. Show students the magic window, which will allow them to see what Balanced Rock looked like in the past. Take students to the correct spot to stand so they can take turns looking through the window. Hold up the window and demonstrate how to close one eye and move their head until Balanced Rock in the window matches Balanced Rock in real life. Have students search for an object in the window but missing in real life. Remind students not to share their findings. Once everyone has taken a turn, ask someone from the group to point to what they noticed is different now. Discuss how very slowly, over time, weathering and erosion weakened the pedestal chip was sitting on, and one day Chip came crashing down. Explain that Chip falling was a fast change, but the changes leading up to its fall were slow. Show them the historic photo of Balanced Rock and point out the boulders below Balanced Rock are not in the photo and ask where they came from. Ask if they notice any similarities between Balanced Rock and Chip. Ask if any other balancing rocks are in the area. (5 min)
5) Have students pose in a crazy shape, trying to mimic Balanced Rock. See if they can hold their pose for ten seconds or if they will fall down like Chip. For those still standing, ask if they could hold this pose forever? At the end, invite everyone to fall down like Chip. Tell them that, just like Chip and like you, Balanced Rock can’t hold its pose forever and will one day fall. (2-3 min)
POST-TRIP ACTIVITY
My Park
STEM Design Challenge: What landforms make up a park?
My Park
STEM Design Challenge: What landforms make up a park?
Procedure:
1) Review field trip stations with students. For example: ask students if they can remember learning about a fragile microscopic organism that helps to prevent erosion. Ask students how the landscape at Arches changes? Ask them to name and describe landforms seen at Arches. (3-5 min)
2) Remind students there are lots of national parks all over the country. Many national parks have landforms which make them special. For example, Arches has arches, and Canyonlands has big canyons. Show them pictures of other national parks containing different landforms. Read the names of the landforms shown in the pictures out loud and describe what makes each park unique. (3-5 min)
3) Tell students they will create their own imaginary national park. Each park should include one super special landform or collection of landforms. Invite the students to use their imaginations. Their landform can be in the shape of an animal, food, or anything else. Give students time to think and imagine.
4) Tell students that once they get their worksheets, they will write their name on the top. Next, have students check the landform(s) they will include in their park on their worksheet. Students should then draw the landform(s) that make their national park special. If time, they can add details to their drawings, such as people swimming, hiking, or riding their bikes. Students should name their park. (10-15 min)
5) Select a few students to share their national park with the class and discuss the landforms found there. Have students put down their pencils so they can focus on listening. Demonstrate how to present work to the class by holding their drawing up high and moving it around slowly. (You can also allow students to do a gallery walk to see all examples, and then call on volunteers to share one of the parks they would like to visit). For each park shared, talk about how fun it would be to visit their park. (5-7 min)
References & Resources
Baylor, B. (1974). Everybody needs a rock. Illus. by P. Parnall. New York, NY: Macmillan Publishing.
Bramwell, M. (1983). Understanding & collecting rocks & fossils. London, England: Usborne Publishing.
Caduto, M. & Bruchac, J. (1988). Keepers of the Earth: Native American stories and environmental activities for children. Golden, CO: Fulcrum.
Cole, J. (1987). The magic school bus: Inside the Earth. Illustrated by B. Degen. New York, NY: Scholastic.
Gans, R. (1984). Rock collecting. Illustrated by H. Keller. New York, NY: HarperCollins Publishers.
Hyler, N. W. (1987). The how and why wonder book of rocks and minerals. Los Angeles, CA: Price, Stern, Sloan Publishers.
Langley, A. (2009). Metal. New York, NY: Crabtree Publishing.
Shaddock, Whitney. Build an island stem challenge. http://www.thefirstgraderoundup.com/2018/08/landforms-stem-ideal-island.html
Williams, D. (1997). Geology: Arches National Park. Moab, UT: Canyonlands Natural History Association. Brochure.
Williams, D. (2000). A naturalist’s guide to canyon country. Helena, MT: Falcon Publishing.
Great Basin Observatory. Playdough Landforms https://greatbasinobservatory.org/lesson-plans/playdough-landforms
Last updated: April 8, 2022