Weathering and Erosion Application Sequence

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Weathering and Erosion Application
Sequence
Part I: Information about the Lesson and
Unit
Topic: Weathering and erosion, part of a unit on weathering and soil.
Abstract
In this three-day application sequence we will introduce the problem of how weathering
and erosion shape the surface of the earth. On day one we will watch and discuss a video to make
sure the students can differentiate between weathering and erosion. We will then introduce two
PEOE activities and use one of them to model an explanation of rockslides using weathering and
erosion. We will coach the students in developing a good explanation for the second PEOE by
giving them criteria for a complete response and walking around answering questions. On day
two, the students will move through lab stations that exhibit more weathering and erosion
examples and develop their own explanations for each activity. On day two we will coach by
providing criteria for a complete response, and by stopping the class periodically to check that
their responses have all of the criteria. On the final day, we will fade and students will need to
develop good explanations for real world geological features.
Part II: Clarifying Your Goals for the Topic
A. Big Ideas
Earth’s systems are dynamic; they interact over a wide range of temporal and spatial scales and
continually react to changing influences, including human activities. Components of Earth’s
systems may appear stable, change slowly over long periods of time, or change abruptly (ESS2A). Earth’s surface is impacted by large time and spatial scale sub-surface processes (plate
tectonics) and small time and spatial scale surface processes (weathering and erosion).
Water plays an important role in shaping Earth’s surface. It participates both in the dissolution
and formation of Earth’s materials. The downward flow of water, both in liquid and solid form,
shapes landscapes through the erosion, transport, and deposition of sediment. Water’s
movements—both on the land and underground—cause weathering and erosion, which change
the land’s surface features and create underground formations (ESS2-C).
Weathering is the breaking down of rock into smaller pieces. Over time, rocks crack, crumble,
and are broken up by water and wind. Drops of water on a rock may repeatedly freeze and melt,
causing the rock to crack. Water may react with some of the chemicals in a rock and cause part
of the rock to break down. Rocks sometimes fall from higher places, breaking as they fall. Small
animals and the roots of plants also contribute to the weathering of rock when they burrow into
the ground. Weathering forms sediments that can be moved by wind and water.
Erosion is the movement of sediments from one place to another by water, wind, or ice. When
water erodes the earth’s surface, it cuts into the ground, forming surface channels. These
channels can range from tiny depressions in the earth to huge canyons, such as the Grand
Canyon. Slow and steady water erosion over long periods of time has created valuable features
of the earth’s landscape such as lakes, rivers, hills, canyons, and fertile plains.
1. Naming key practices
On day one, we establish the problem “How does weathering and erosion shape the surface of
the Earth?”. Our goal is to use weathering and erosion (the model) to explain some of the various
geological features on Earth (using models 2b and constructing explanations 6). Students should
have prior knowledge of the model (weathering and erosion) from previous classes so we spend
less time developing knowledge. The three days are meant to have students practice using the
model and understand how it can be used to explain many different observations, geological
features on Earth (constructing explanations 6).
The mini PEOE will have students Predict, Explain, Observe, and Explain what happens when
we shake a container of sugar cubes and pebbles. This is the left arrow, inquiry: developing
knowledge. Students are asking questions (1), carrying out investigations (3), analyzing and
interpreting data (4). The teacher will model how to engage in argument from evidence (7) so
this is not a true PEOE as we are also using this activity as part of our modeling in the EMCF
sequence, which will take place over the 3 days.
General Practices:
During our lessons, students will obtain, evaluate, and communicate information (8) both orally
and in writing.
C. Performance Expectations for Student Learning
Performance Expectation
Associated
NGSS
Practice
NGSS Performance Expectation(s)
1. Construct an explanation based on evidence for how geoscience processes
have changed Earth's surface at varying time and spatial scales. (MS-ESS22)
Constructing
explanations (6)
Clarification Statement: Emphasis is on how processes change Earth’s surface at time and
spatial scales that can be large (such as slow plate motions or the uplift of large mountain
ranges) or small (such as rapid landslides or microscopic geochemical reactions), and how
many geoscience processes (such as earthquakes, volcanoes, and meteor impacts) usually
behave gradually but are punctuated by catastrophic events. Examples of geoscience
processes include surface weathering and deposition by the movements of water, ice, and
wind. Emphasis is on geoscience processes that shape local geographic features, where
appropriate.]
2. Develop a model to describe the cycling of Earth's materials and the flow
Developing
of energy that drives this process. (MS-ESS2-1) [Clarification Statement: Emphasis models (2a)
is on the processes of melting, crystallization, weathering, deformation, and sedimentation,
which act together to form minerals and rocks through the cycling of Earth’s materials.]
[Assessment Boundary: Assessment does not include the identification and naming of
minerals.]
Specific Lesson Objective(s)
1. Construct an explanation on how weathering and erosion shape Earth’s
surface resulting in various geological structures.
Constructing
explanations
(6)
Part III: Classroom Activities
A. Storyline for the Lesson Sequence
Stage
Role in Storyline
Lessons before
your sequence
Students will have prior knowledge about weathering and erosion as
they will have finished the chapter “Weathering and Soil” in their book
and it’s related worksheets and activities. They have some more
familiarity with Erosion on a previous unit on the Rock cycle.
Section 1 of the chapter deals with weathering. They learn that
weathering processes weaken and break apart rock material into smaller
pieces. The should be able to differentiate between chemical and
mechanical weathering. The chapter also briefly touches on the fact that
weathering shapes Earth’s surface which is the topic we focus our 3 day
lesson on.
Section 2 and 3 focus on Soil- its nature and its erosion. The should
understand that soil is a mixture of weathered rock, decayed organic
matter, mineral fragments, water, and air. They should also know that
soil erosion is harmful because plants do not grow as well when topsoil
has been removed.
Lesson 1
We will address the difference between weathering and erosion in order
to connect with previous lessons and reinforce the idea that the processes
are unique from each other. We will then introduce the problem of how
the earth is continually being shaped by the two processes. By shaking
sugar cubes in a can, we will demonstrate how rock slides shape rocks.
We can say that it is analogous to pebbles getting worn down in a
streambed, but in that case the medium transporting the pebbles is water.
Then, we will model a complete explanation of this example for the
students.
Lesson 2
The students will visit four lab stations and observe different forms of
weathering and erosion. They will use their observations to conduct
quality explanations for the processes happening at each station. We will
move from group to group ensuring that they are writing good
explanations, and their packets will have scaffolding (specific response
criteria).
Lesson 3
Students will investigate real world geological features as case studies.
They will construct explanations for how the features form. They have
had practice constructing explanations for the activities in day two, so
they will apply this practice to the case study. We will fade by checking
in periodically with individuals, but no longer for each example.
Lessons after
your sequence
After our sequence, students will come back from spring break and
begin a unit on soil and fossils.
B. Activity Sequence Details
Focus Objective
Objective
1. Construct and explanation on how weathering and erosion change
the appearance of Earth’s surface.
1. Application Cycle
Examples and Scaffolding (Pattern in Student Practices)
List of examples
1. The rounding of rocks in landslides using the sugar cube experiment.
2. Chemical/mechanical weathering with bar of soap.
3. Rock slide video
NGSS Practice
Constructing
explanations (6)
Stations:
4. Pouring water on a pile of sand.
5. Blowing sand
6. Ice wedging
7. Adding pipe cleaners to sand to reduce soil erosion
Case studies:
8. Cliff Collapse
9. Jump-Off Joe
10. Land Slide in Italy
11. The Dust Bowl
12. Michigan Potholes
Scaffolding that applies to all examples
Each explanation should include:
● The name of the process involved (erosion and/or the specific type of weathering)
● A drawing that shows the movement of the rock material with arrows (when applicable)
and the weathering agent (wind, water, ice)
● A written explanation of what is happening in the drawing
Stages in Your Application Cycle
Stage
Teaching Activities
Establishing the The world is constantly being changed by the processes of weathering
problem
and erosion. How can we explain some of the geological features on the
surface of the Earth today?
Modeling
We will develop an explanation on the board for the sugar cube
demonstration (one of the two PEOE’s).
Coaching
On day 1, each student will write an explanation for the bar of soap
example (one of the two PEOE’s). We will write the criteria for a good
explanation on the board, and we will walk around answering questions.
On day 2, groups will observe different forms of weathering and erosion
and write explanations of how they are influencing the material in each
model. Again, students will be given our criteria and we will be
checking in with the class to make sure they are writing complete
responses.
Fading
The students will examine case studies and write explanations using the
processes of weathering and erosion to explain the formation of many
prominent surface features. The worksheet does not repeat the criteria
for each example (only the first one), and we will gradually reduce how
often we address the whole class to give reminders.
Maintenance
We did not plan maintenance explicitly into this lesson, but if we can get
through all of the examples on day 3 then our fading may lead to
maintenance.
C. Lesson Plans
Lesson 1 Materials
Presentation materials (Overhead
transparencies or PowerPoint presentations,
etc)
Scaffolding criteria written on the board (so
that we can use the overhead and still be able
to point to the criteria).
Copied materials (Handouts, worksheets,
tests, lab directions, etc.)
Lesson 1 worksheet (see
Lesson1_WeatheringErosion.docx attached)
Laboratory materials:
(For the teacher or the class as a whole)
- 10 Sugar cubes
- 10 pebbles/rocks
- Jar with lid (tupperware or coffee canister
work fine)
-One bar of soap
Other materials:
Weathering and Erosion video from
StudyJams:
http://studyjams.scholastic.com/studyjams/ja
ms/science/rocks-mineralslandforms/weathering-and-erosion.htm
Rock slide video:
https://www.youtube.com/watch?v=B4RYtNJpdL
Y
Lesson 1 Activities
Lesson 1 Introduction (10 minutes)
● Establishing the Problem
○ We will show a compilation of pictures of interesting land formations from
National Geographic’s weathering and erosion photomontage, and then say that
the goal for the day is to explain surface features using weathering and erosion.
○ On the board, we will have the 3-day lesson’s objective and the day’s activities.
We will make the objective clear: “During the next three days, your goal it to be
able to explain how weathering and erosion shape Earth’s surface”.
Show video to help students better understand the difference between weathering and erosion
and how they work together.
● Weathering and Erosion video from StudyJams:
○ http://studyjams.scholastic.com/studyjams/jams/science/rocks-mineralslandforms/weathering-and-erosion.htm
○ Review of previous lessons. This should help students review and understand the
different vocabulary (mechanical weathering, chemical weathering, erosion) and
understand how weathering and erosion are a “superduo” and work together to
form Earth’s surface
●
Set up the bar of soap PEOE. The Instructor should show students the new bar of soap,
and say that you will place it under the faucet for the entire class period, with the faucet
dripping very slowly. Ask students to write their prediction of what the soap will look
like at the end of the class period, and to explain why. We will return to this at the end of
class.
Lesson 1 Main Teaching Activities (30 minutes)
● Modeling
○ Materials
■ 10 Sugar cubes
■ 10 pebbles
■ Jar with lid (tupperware or coffee canister work fine)
○ Put 10 sugar cubes and 10 pebbles into the container and put on lid.
● Explain to students that rocks can be broken down when they tumble down a mountain.
○ Ask “What causes the rock to first go down the mountain?”
■ Students might explain earthquakes, rain, someone pushes it…
■ Explain that gravity is always pulling down on us. So yes, rocks can be
broken down by weathering and these new fragments of rocks might
become unstable and gravity now pulls them down the slope of the
mountain.
● Ask “What is another way that rocks can get broken down?”
■ Transport in water by rivers and streams. The rocks tumble against each
other and get smoothed down.
● We are going to explore what happens as these rocks fall down the mountain by taking
some sugar cubes and pebbles and shaking them in this container.
○ Explain that the sugar cubes represent a softer rock (like limestone) but we are
using sugar cubes in order to see a result in less time.
○ Select 2 students to shake the container. (or pass the container around the class?)
● As we are waiting, I want you to predict what is going to happen to the sugar cubes and
the rocks and why. We will walk around and check your predictions.
○ Select 2 students to replace original volunteers so that they have a chance to write
their predictions.
● Show the contents of the tupperware on the overhead. Put the now rounded sugar cube
next to an untouched one.
● Ask students to describe their observations. What happened to the sugar cubes?
● Every rock tells a story.
○ This activity showed that rocks can be worn down by the direct actions of other
rocks.
○ What if we kept shaking the container, what might happen (the sugar cubes would
become smaller and rounder)? What if we shook it for a few months, a few years
(the pebbles would start to break down as well)?
● Model a good response on the overhead (see scaffolding below). Explain the components
of our scaffolded response and why we included each part.
○ Scaffolding that applies to all examples
■ Each explanation should include:
●
●
●
A drawing that shows the movement of the rock material with
arrows (when applicable) and the weathering agent (wind, water,
ice)
The name of the processes involved (erosion and/or the specific
type of weathering)
A written explanation of what is happening in the drawing
●
Show this video of a real rock slide (starting at 1 min.).
https://www.youtube.com/watch?v=B4RYtNJpdLY
○ Coach a good response on the overhead (see scaffolding above) as a class. Call on
students to contribute parts of the response. Encourage class discussion (ex. does
anyone disagree?, does anyone want to add something?, can you explain
more…?) Make sure students explain the components of our scaffolded response
and why we included each part.
Lesson 1 Conclusion (10 minutes)
●
Show the bar of soap of the overhead, and ask students to write their observations.
Pass the soap around the room as well. Then, ask them to write an explanation of what
they observed following the scaffolding criteria on the board. Collect this explanation
before they leave.
Lesson 2 Materials
Presentation materials (Overhead
transparencies or PowerPoint presentations,
etc)
Copied materials (Handouts, worksheets,
tests, lab directions, etc.)
Worksheets with lab directions and questions
Laboratory materials:
For the teacher or the class as a whole:
For each laboratory station:
Station 1: tub, sand, water, small pitcher
Station 2: cake pan, cardboard, sand
Station 3:
Ahead of time, the teacher prepares two
containers filled with plaster of paris. One
with a balloon filled with water (size of a golf
ball) and nothing in the other.
At the station: 2 milk cartons (one cracked
with remnants of balloon) filled with plaster,
explanation of the experiment
Station 4: cake pan, sand, bucket/sink (with
filter to collect sand), water, small water
pitcher, pipe cleaners
Other materials:
Lesson 2 Introduction (8 minutes)
● Review student responses to the bar of soap example. Go over example responses (one
poor, one medium, and one good) and remind the class what constitutes a complete
response.
● Divide students into groups for lab activity
Lesson 2 Main Teaching Activities (40 minutes)
4 stations:
1) Pouring water on a pile of sand
Students will pile up sand in a tub. They will make initial observations of the sand and record
them. Students will then pour water over the pile of sand. They will try to pour the water so it
hits the same area on the pile the whole time. They will then record their observations and
record them. With their notes they will construct good explanations for the processes they
observe.
2) Blowing sand
Place a pile of sand in a cake pan with cardboard as a back-stop so the sand does not blow away.
Have the students blow on one side of the pile. Make sure they record the pile before and after
the students blow on the sand. Using their notes, the students will construct a good explanation
for wind erosion.
3) Ice wedging
Ahead of time, the teacher prepares two containers filled with plaster of paris. Put a balloon
filled with water (size of a golf ball) in one and nothing in the other. Let the containers cool in
the freezer overnight. The plaster containing the balloon should have cracked as the water in the
balloon froze and expanded.
4) Erosion and plants
How plants help reduces erosion
1. Smooth out the sand in the cake pan. Make sure the walls of the pan are at least 1 inch
above the level of the sand.
2. Place an object ½ inch thick under one end of the pan and have the other end over a sink.
3. Slowly pour water in at the end of the elevated sand and record your observations
4. Smooth out the sand and place 15 pipe cleaner in the sand to simulate vegetation
5. Pour water in the pan again like before and record your observations.
As water ran over the soil, it carried away the sediments formed by weathering which will form
gullies in the soil and rocks. Running water eroded the rock and digs gullies in the ground.
Adding grass on top of the soil keeps the water from digging a gully. This is because the roots of
the plants hold the soil together so that erosion cannot take the soil away.
Lesson 2 Conclusion (2 minutes)
●
●
Have each group clean up their station and make sure it is ready for the next class
Collect the lab packet on their way out
Lesson 3 Materials
Presentation materials (Overhead
transparencies or PowerPoint presentations,
etc)
Powerpoint with case study examples
(CaseStudies_day3.pptx)
Copied materials (Handouts, worksheets,
tests, lab directions, etc.)
Worksheet: Lesson3_WeatheringErosion.docx
Laboratory materials:
For the teacher or the class as a whole:
For each laboratory station:
Other materials:
Weathering and Erosion Song
https://www.youtube.com/watch?v=2311yO5
opVk
Lesson 3 Introduction (10 minutes)
● Video about the formation of the Grand Canyon:
https://www.youtube.com/watch?v=ktf73HNZZGY
○ Remembering previous lessons: Remind students of the “superduo Breaker and
Whoosh”. What did Breaker represent? Weathering. So what does Breaker do?
Breaks rocks. What was an example of weathering in this video? The Colorado
River, rock slides, etc.. And what was Whoosh? Erosion. And what did he do?
Carry the rocks/sediments away. What was an example of erosion in this video?
Transported sediment in the Colorado River and the streams that feed into it.
○ Ask students about other ways rock can be weathered and eroded that they have
learned about during the previous two lessons. Allow time for them to share their
ideas.
● Review student responses to one of the station examples. Go over one poor, one
medium, and one good response, and remind the class what constitutes a complete
response.
Lesson 3 Main Teaching Activities (35 minutes)
In this part of the lesson we will have five “case studies” of earth’s surface features that can be
explained by weathering and erosion. Students will be asked to write scientific explanations for
what they observe about each case study. We plan to show the scaffolding criteria for the first
one, but then not for the last four. The instructors will walk around checking student
explanations, but we will not provide as much support as Lesson 2. We plan to have students
check their responses with a partner for the first three case studies, but the last two will be
entirely on their own. Pictures and assessment questions can be found on the powerpoint.
●
●
●
●
●
#1 Two Mountains
#2 Jump-Off Joe
#3 Land Slide in Italy
#4 The Dust Bowl
#5 Michigan Potholes
Lesson 3 Conclusion (5 minutes)
● Explain that we focused mainly on erosion and mechanical weathering but there’s also
chemical weathering.
● Show video/song to summarize weathering and erosion
○ https://www.youtube.com/watch?v=2311yO5opVk
● Collect the worksheets
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