MS-ESS2-2NGSS*ScienceEarth and Space ScienceGrades 6-8
MS-ESS2-2: Explaining How Earth's Surface Changes, Fast and Slow
In plain English: MS-ESS2-2 is the NGSS middle school performance expectation that asks students to construct an evidence-based explanation of how geoscience processes, such as weathering and deposition by water, ice and wind, have changed Earth's surface over times from seconds to millions of years and over areas from tiny grains to mountain ranges. It is usually taught in grade 6, 7 or 8 Earth science.
Construct an explanation based on evidence for how geoscience processes have changed Earth's surface at varying time and spatial scales.
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.
Next Generation Science Standards · Disciplinary Core Idea: Earth's Systems · Official standard
Students construct scientific explanations, based on evidence, for how Earth's surface has changed. A geoscience process is a natural process that changes the land, such as weathering (breaking rock down where it sits), erosion (carrying the pieces away) and deposition (dropping them in a new place), as well as uplift, earthquakes, volcanoes and meteor impacts. Students compare processes at different time scales (how long a change takes, from seconds to millions of years) and spatial scales (how large an area it changes, from microscopic grains to whole mountain ranges). They also see that many processes work gradually, little by little, and are interrupted now and then by sudden, catastrophic events such as floods, landslides and impacts. Each explanation follows a claim, evidence and reasoning frame: a claim about what happened, data or observations as evidence, and reasoning that links the two.
The NGSS Clarification Statement says: "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." MS-ESS2-2 has no official Assessment Boundary. This page works through weathering and deposition by water, ice and wind, and adds slow uplift and sudden floods, landslides, earthquakes and one meteor impact. Every data set is invented for teaching, uses realistic rates and is labeled as invented, except the few facts about Meteor Crater in Arizona. Teachers are encouraged to swap in a landform near their school.
Learning Objectives
By the end of this lesson, students will be able to:
Describe how water, ice and wind weather rock and deposit sediment, and name evidence each one leaves behind
Compare geoscience processes by time scale (seconds to millions of years) and spatial scale (grains to mountain ranges) using rates and data
Explain how gradual processes can be interrupted by catastrophic events such as floods, landslides and impacts
Construct a claim, evidence and reasoning explanation for how a landform or local feature changed
Prior Knowledge Required
Students should already be comfortable with:
Observing and measuring weathering and erosion by water, ice, wind or plants 4-ESS2-1
Using rock layers and fossils to explain changes in a landscape 4-ESS1-1
Rates such as meters per year, and converting meters, kilometers and millimeters
Show two photos side by side: a smooth, rounded river pebble and a fresh pile of broken rock at the bottom of a cliff. Do not say how either formed.
Warm-Up Prompt
"One of these changes probably happened in a few seconds and the other took thousands of years. Which is which? What clues in the photos are you using?"
List the clues on the board in two columns, "fast" and "slow". Students often say the rounded pebble was "always round". Ask what could knock its corners off. Tell students that today they will make claims like these and back them with evidence.
Direct Instruction15-20 minutes
Processes, scales and evidence. Water, ice and wind are the three main movers at Earth's surface. Each one can weather rock, erode it and deposit it somewhere else. To compare processes, scientists ask two questions: How long does the change take? How large an area does it change? Diagram 1 places the processes from the examples below on one time line. Because the times range from seconds to hundreds of thousands of years, the time line uses a powers-of-ten scale, where each step multiplies the time instead of adding to it. Use Diagram 2 to show a gradual process interrupted by a sudden event.
Weathering by water: a slow, microscopic reaction
Invented data: a marble gravestone carved in 1870 was measured in 2020. Its flat top had been lowered by 1.5 mm. A slate gravestone carved the same year has lost less than 0.1 mm.
Result: Rate = 1.5 mm ÷ 150 years = 0.01 mm per year, or 1 mm per century. Rain is slightly acidic (carbon dioxide from the air dissolves in it), and it reacts with the marble one tiny grain at a time. Slate barely reacts, so rock type matters.
Deposition by wind: a moving sand dune
Invented data: the crest (top edge) of a dune was measured from a fence post each year: 0, 15, 28, 44 and 58 m. A road lies 116 m beyond the crest's last position.
Result: Rate = 58 m ÷ 4 years = 14.5 m per year. Time to reach the road = 116 ÷ 14.5 = 8 years. Wind carries sand up the gentle side and drops it on the steep side, so the whole dune creeps forward.
Weathering and deposition by ice: a glacier
Invented data: glacier ice in a valley moves 0.5 m per day. A granite boulder sits on limestone bedrock 36.5 km from the nearest granite, next to bedrock covered with parallel scratches.
Result: Speed = 0.5 × 365 = 182.5 m per year. Time to carry the boulder 36,500 m = 36,500 ÷ 182.5 = 200 years. Rocks frozen into the moving ice scratched the bedrock, and the melting ice dropped the boulder far from where it started.
Gradual deposition punctuated by a flood
Invented data (Diagram 2): new sediment measured each year on the floor of a reservoir: 2.0, 1.8, 2.3, 1.9, 2.1, 1.7, 35.0, 2.4, 2.0 and 1.8 cm. The 35.0 cm layer was laid down during a flood that lasted three days.
Result: Total = 53.0 cm. The flood layer is 35.0 ÷ 53.0 ≈ 66% of all the sediment, laid down in days. The other nine years average 18.0 ÷ 9 = 2.0 cm per year.
A catastrophic event: Meteor Crater, Arizona
Real data, rounded: Meteor Crater is about 1.2 km across and about 170 m deep. It formed about 50,000 years ago when a meteorite hit northern Arizona, then a cooler, wetter land of grassland and woodland, and the blast dug out the crater in seconds.
Result: One event changed an area more than 1 km wide in seconds. In the 50,000 years since, slow weathering and erosion have worn down the rim and partly filled the floor, but the crater is still clear: evidence that the gradual processes there are slow.
After each example, ask: "What is the claim? Which numbers or observations are the evidence? Is this change sudden or gradual, small or large?" Point out that a sudden event can change a large area (the crater) and a gradual process can change a small area (the gravestone), so speed and size are separate questions.
Guided Practice10-15 minutes
Pairs use the invented rates below to compare time scales. For each process they find how long it would take to move material (or raise the land) by 1 km, then order the processes from fastest to slowest.
Guided practice: invented rates for five processes
Process
Agent
Invented rate
Pebbles pushed along a creek bed during a storm
Water
40 m per hour
Ice flowing down a mountain valley
Ice
0.3 m per day
Crest of a sand dune moving downwind
Wind
12 m per year
Front edge of a river delta growing into a lake
Water
25 m per year
A mountain range being pushed upward
Earth's internal forces
4 mm per year
Convert 1 km to meters (or millimeters for the mountain range) and divide by each rate. Keep the time unit of the rate.
Change each answer into years where needed so the times can be compared: the creek takes about 25 hours, and the glacier about 3,300 days, or about 9 years.
Order the five processes from fastest to slowest and mark which ones are weathering or erosion and which are deposition.
Write one sentence: which process would you need the most evidence for, and why can't anyone watch it happen?
Independent Practice10-15 minutes
Each student writes a claim, evidence and reasoning explanation for the invented beach data below. The beach width was measured every September from the sea wall to the water line. A large winter storm hit between the 2017 and 2018 measurements.
Independent practice: invented width of the beach at Gull Point
Year
2016
2017
2018
2019
2020
2021
2022
Width (m)
60
61
42
44
46
48
50
Students should find that the storm removed 19 m of beach in one season, while waves have been depositing sand back at about 2 m per year. Ask them to predict when the beach will return to its 2017 width if the trend continues, and to name the process behind each change (erosion by storm waves, deposition by gentle waves).
Closure5 minutes
Exit ticket: "Name one change to Earth's surface that can happen in seconds and one that takes millions of years. For each, give one piece of evidence you could see in the landscape." Return to the warm-up photos and ask students to rewrite their clues as evidence statements.
Differentiation Strategies
For Struggling Students
Give a claim-evidence-reasoning frame: "I claim ___ changed this landform. The evidence is ___. This supports my claim because ___."
Provide a conversion card (1 km = 1,000 m = 1,000,000 mm; 1 year = 365 days) for the rate problems
Sort the evidence cards first by agent (water, ice, wind, gravity) before sorting by time scale
For Advanced Students
Ask students to find a landform near the school on a map and write a full explanation with at least two processes at different scales
Have students estimate how many "normal" years of sediment the reservoir flood in Diagram 2 equals, and discuss why averages can hide sudden events
Ask students to research how scientists date the Meteor Crater impact, and explain why the age is given as "about" 50,000 years
Assessment Guidance
What to Look For
Check that each explanation names a process and an agent (water, ice or wind), not only a landform. Look for evidence statements that use measurements or observations, and reasoning that links them to the claim. Listen for students who think all big changes must be fast or that slow processes cannot make large features, and check unit conversions in rate problems.
02
Classroom Activities
3 Activities
1
Shake Test: How Moving Water Rounds Rock
20 minGroups of 3-4
Groups model the weathering of rock fragments as a river tumbles them. They shake sugar cubes in a plastic jar, measure the mass lost after each set of shakes and watch the corners round off. The sugar cubes stand for angular rock fragments, and the shaking stands for river water knocking them together.
Procedure
Find the mass of 10 sugar cubes on the scale and sketch one cube.
Put the cubes in a dry plastic jar, screw the lid on and shake hard 100 times. Pour them onto a paper towel, brush off the loose powder and find their mass again.
Repeat for a second and third set of 100 shakes, sketching one cube each time.
Do not eat the sugar cubes, and wipe up all loose sugar at the end.
Sample Data (invented)
Mass of 10 cubes: 30.0 g at the start, 27.6 g after 100 shakes, 25.5 g after 200 shakes and 23.8 g after 300 shakes.
Discussion Questions
Which set of 100 shakes removed the most mass, and why might the first set remove more than the later ones?
What percent of the starting mass was lost after 300 shakes?
A geologist finds well-rounded pebbles far downstream and angular rock near the cliff they came from. Use your data to explain the difference.
Challenge Variation
Add a handful of aquarium gravel to a second jar with 10 new cubes and repeat. Predict, then test, whether harder "rock" in the water makes the cubes lose mass faster.
2
Wind and Ice Stations
25 minPairs
Pairs visit two stations that model the official examples of weathering and deposition by wind and by ice. At the wind station they blow sand into a small dune; at the ice station they drag a block of gritty ice across clay and see what it leaves behind when it melts.
Procedure
Wind station: wear goggles. Make a low mound of sand about 3 cm high in a shoebox lid. Kneel behind one end of the box and blow gently through your own straw, 20 puffs at a time, aiming away from other people. Each student uses a new straw; never share straws. Mark the position of the crest with a ruler after 20, 40 and 60 puffs, and sketch the shape of both sides.
Ice station: press an ice block with sand and gravel frozen into its bottom onto a flat clay slab and push it slowly across the clay 5 times. Look at the clay with a ruler beside it. Leave the block at the end of the slab on a tray and check it again at the end of class.
Wipe up melt water and spilled sand right away so the floor does not get slippery.
Sample Data (invented)
Wind station: crest moved 4 cm after 20 puffs, 9 cm after 40 puffs and 13 cm after 60 puffs. The upwind side had a gentle slope and the downwind side a steep one. Ice station: 7 parallel scratches up to 2 mm deep; after melting, a heap of mixed sand and gravel with no layers.
Discussion Questions
Did the crest move about the same distance for each set of 20 puffs? What does that suggest about a dune in a steady wind?
The ice left an unsorted heap of mixed grain sizes, but sand from your dune is all the same size. How could this help you tell deposits made by ice from deposits made by wind?
Real glaciers move a few centimeters to a few meters per day. What does your model speed up, and what does it leave out?
Modification for Distance Learning
Students use flour or sugar on a baking tray and a paper fan for the wind station, and freeze a little sand in a paper cup for the ice station, then post photos with labels.
3
Constructing an Explanation: The Story of Cedar Valley
20 minGroups of 3-4
Each group gets 8 invented evidence cards from Cedar Valley, a made-up valley with a river and a lake. Groups sort the cards by process and scale and then write one explanation of how the valley got its shape. Teachers can replace the cards with photos and data from a landform near the school.
Evidence Cards
Parallel scratches on bare bedrock, all pointing down the valley
A house-sized granite boulder resting on limestone bedrock; the nearest granite is 30 km up the valley
A low ridge of mixed clay, sand and boulders running across the valley floor
The valley has a U-shaped cross-section with steep walls
A fan of broken rock at the foot of a cliff that was not there 3 years ago
Rounded gravel in layers in a road cut, 10 m above today's river
A delta where the river enters the lake, growing about 20 m per year
A marble statue in town, carved in 1920, with shallow, worn letters
Procedure
For each card, record the agent (water, ice, wind or gravity), whether it shows weathering, erosion or deposition, and whether the change was sudden or gradual.
Place each card on a time line from "seconds" to "millions of years" and label its size: grains, a few meters, a valley, or a whole region.
Write a claim, evidence and reasoning explanation that uses at least four cards.
Discussion Questions
Which card shows the only sudden event, and what evidence tells you it was sudden?
Cards 1-4 point to the same agent. Which one, and how long might it have taken to carry the boulder on Card 2 at 0.4 m per day?
Which card shows a process happening at a microscopic scale?
Modification for Distance Learning
Post the cards on a shared slide. Each group drags them onto a time line and records a two-minute explanation as a voice note.
03
Diagrams & Visual Aids
2 diagrams
Diagram 1: How Long Each Change Takes, from Seconds to Millions of Years
The processes from the worked examples and guided practice on a powers-of-ten time line, positioned by computing each time in seconds. Dark points are sudden events; blue points are gradual processes. The impact crater, a sudden event, changed a larger area than the dune crest, which shows that time scale and spatial scale are separate questions. Rates are invented except the impact.
Diagram 2: Gradual Deposition Interrupted by One Flood (Invented Data)
New sediment on the floor of an invented reservoir, measured each year for 10 years and drawn to scale. Nine years add about 2 cm each, but one three-day flood in Year 7 added 35.0 cm, about two thirds of the 10-year total.
04
Homework Assignment
~30 min
MS-ESS2-2 Homework: Explaining Changes to Earth's Surface
Directions: All data are invented for practice. Show each calculation with units. For every explanation, give a claim, the evidence (numbers or observations) and reasoning that connects them. Use 365 days in a year.
Part 1: Rates and Scales (Problems 1-3)
A glacier in a mountain valley moves 0.2 m per day. A boulder of basalt sits on sandstone 21.9 km from the nearest basalt. (a) How far does the glacier move in a year? (b) How long would it take the glacier to carry the boulder 21.9 km? (c) Give two observations that would show ice, not a river, moved the boulder.
In one cemetery, a marble gravestone has lost 2.4 mm of its surface in 200 years, and a slate gravestone the same age has lost 0.2 mm. (a) Find each rate in millimeters per century. (b) How many times faster is the marble weathering? (c) At its rate, how long would the marble take to lose 1 cm? (d) Explain why this is a process at a microscopic spatial scale even though you can see the result.
The crest of a dune was 0, 9, 17, 27 and 36 m from a fence post in five yearly measurements. (a) Find the average rate the dune moves. (b) A house stands 153 m beyond the crest's last position. About how many years until sand reaches it? (c) Explain how wind moves and deposits the sand.
Part 2: Gradual and Catastrophic Change (Problems 4-5)
A 50 cm core of lake mud contains one 14 cm layer of sand from a single flood. The rest is made of thin yearly layers that are each about 1.5 mm thick. (a) How many years do the yearly layers cover? (b) What percent of the core's thickness came from the flood? (c) A student divides 50 cm by the number of years and calls it "the normal rate." Explain why that rate is misleading.
A coastline is rising about 4 mm per year. During one earthquake, it rose 2 m in a few seconds. (a) How many years of gradual rise equal the one earthquake? (b) Use this example to explain what "gradual processes punctuated by catastrophic events" means.
Part 3: Construct an Explanation (Problem 6)
Choose a landform near your home or school, or use invented Pine Ridge: rounded gravel in layers in a road cut above today's river, a fan of broken rock at the base of a cliff, and sand drifted against a fence. Write a claim, evidence and reasoning explanation of how the landform changed. Name at least two processes, the agent of each, whether each was sudden or gradual, and its time and spatial scale.
Rubric
Criterion
Full Credit (2 pts)
Partial Credit (1 pt)
Rates and Conversions
Rates and times correct with units, including meters to kilometers and days to years
Correct method with one conversion or calculation error
Processes and Agents
Names weathering, erosion or deposition and the agent (water, ice or wind) for each change
Names the process or the agent but not both
Scales
Describes both the time scale and the spatial scale, and whether the change was sudden or gradual
Describes only one scale
Explanation
Claim, evidence and reasoning all present; the reasoning links each piece of evidence to the claim
Claim and evidence present but reasoning missing or general
05
Quiz: 20 Questions
Interactive, with answers
Instructions
All data are invented for practice. Use 365 days in a year. Your score updates as you answer, and Reset quiz clears everything so you or your students can try again.
Multiple choice: pick an option to check it. Short answer: write your answer, then reveal the model answer.
0 of 20 answered · 0 correct
Question 1 of 20 · Multiple Choice
Which change to Earth's surface acts over the largest area and the longest time?
Answer: C
A mountain range rises over hundreds of kilometers and millions of years, so it is large in both space and time. Choices A and B are sudden events in a small area. Choice D is gradual but covers only a small area over years.
Question 2 of 20 · Multiple Choice
Which is an example of a sudden, catastrophic change to Earth's surface?
Answer: A
A landslide moves a large amount of rock and soil in minutes. Choices B, C and D are gradual processes that take years or longer to make a change you can see.
Question 3 of 20 · Multiple Choice
Sand builds up in a long pile against a fence after windy days. Which process is this?
Answer: D
The wind carries sand and drops it where the fence slows the air, which is deposition by wind. Choice B names the wrong agent, and choices A and C describe breaking rock down, not dropping sediment.
Question 4 of 20 · Multiple Choice
Bare bedrock in a valley is covered with long, parallel scratches. What is the best explanation?
Answer: B
Moving glacier ice holds rocks in its base and drags them across the bedrock, leaving long parallel scratches. Choice A is a common confusion: rivers round and polish rock but do not cut straight parallel lines across a valley floor. Choices C and D act grain by grain and leave pits or smoothed surfaces, not long scratches.
Question 5 of 20 · Multiple Choice
Invented data: a dune moves 8 m per year toward a road 96 m away. About how long until the sand reaches the road?
Answer: C
Time = distance ÷ rate = 96 ÷ 8 = 12 years. Choice A multiplies instead of dividing. Choice B subtracts 8 from 96, and choice D adds them.
Question 6 of 20 · Multiple Choice
Invented data: glacier ice moves 0.6 m per day. How far does it move in one year?
Answer: B
Distance = 0.6 × 365 = 219 m. Choice A uses 30 days, one month instead of a year. Choice C divides 365 by 0.6, and choice D adds 0.6 to 365.
Question 7 of 20 · Multiple Choice
Which is an example of a geoscience process at a microscopic scale?
Answer: A
Acidic rain reacts with marble one tiny grain at a time, a chemical reaction too small to see while it happens. Choices B, C and D change areas from hundreds of meters to hundreds of kilometers.
Question 8 of 20 · Multiple Choice
Invented data: new sediment in a lake was 2, 2, 3, 2, 30 and 2 cm in six years. Which statement best explains the data?
Answer: D
Five years add 2-3 cm each, and one year adds 30 cm, so a gradual process was interrupted by a sudden event such as a flood. Choice C is the six-year average (41 ÷ 6 ≈ 7 cm), which hides the pattern. Choice A ignores the spike, and choice B reverses what happened in Year 5.
Question 9 of 20 · Multiple Choice
Invented data: a winter storm removes 24 m of a beach, and gentle waves then add back 1.5 m per year. How many years until the beach recovers?
Answer: B
Years = 24 ÷ 1.5 = 16 years. Choice A multiplies 24 by 1.5. Choice C subtracts 1.5 from 24, and choice D adds them.
Question 10 of 20 · Multiple Choice
Rounded, smooth pebbles are found far downstream from the cliff where the rock broke off. What does this evidence suggest?
Answer: C
As river water carries pebbles, they knock against each other and the riverbed, wearing off their corners over a long distance. Choice D ignores that rock near the cliff is angular. Choice B would leave a mix of angular sizes, and choice A moves only small grains.
Question 11 of 20 · Multiple Choice
Invented data: a 40 cm lake core has one 12 cm flood layer. What percent of the core came from the flood?
Answer: A
Percent = 12 ÷ 40 × 100 = 30%. Choice B writes the 12 cm as a percent. Choice C is the percent from the other layers. Choice D divides 40 by 12 instead of 12 by 40.
Question 12 of 20 · Multiple Choice
Which pair shows the same process, deposition by wind, at a small and a large spatial scale?
Answer: D
Wind ripples a few centimeters apart and a dune field kilometers wide both form when wind drops sand. Choice A mixes chemical weathering by water with ice. Choices B and C pair different processes.
Question 13 of 20 · Multiple Choice
Which evidence best supports the claim that a valley was carved by a glacier rather than by a river?
Answer: C
Glaciers carve broad U-shaped valleys and scratch the bedrock with the rocks they carry. Choice A is the shape rivers usually cut. Choices B and D could form in many valleys, so they do not tell ice from water.
Question 14 of 20 · Multiple Choice
Invented data: a coast rose 1.2 m in one earthquake. Elsewhere, a coast rises gradually at 3 mm per year. How many years of gradual rise equal the earthquake?
Answer: B
1.2 m = 1,200 mm, and 1,200 ÷ 3 = 400 years. Choice A multiplies 1.2 by 3. Choice C uses 12,000 mm for 1.2 m, and choice D uses 120 mm.
Question 15 of 20 · Short Answer
Invented data: the front of a delta was 0, 18, 37, 54 and 72 m from a marker in 2019, 2020, 2021, 2022 and 2023. Find the average rate of growth and predict the position in 2030. Which process is building the delta?
Rate = 72 m ÷ 4 years = 18 m per year. In 2030, 7 years after 2023: 72 + 7 × 18 = 198 m, if the trend continues. The delta is built by deposition by water: the river slows when it enters the lake and drops its sediment.
Question 16 of 20 · Short Answer
A student says, "Only big, sudden events like earthquakes really change the land." Use two examples from this lesson to respond.
Sudden events do change the land (a landslide or an impact crater can change an area in seconds or minutes), but slow processes add up too. A dune moving about 15 m per year can bury a road within a decade, and a mountain range rising a few millimeters per year can rise kilometers over hundreds of thousands of years. Both kinds of change shape the surface, at different time scales.
Question 17 of 20 · Short Answer
A glacier melted away thousands of years ago. Describe two kinds of evidence it might have left behind, and say whether each one comes from weathering or from deposition by ice.
Weathering (and erosion) by ice: parallel scratches on bedrock and a U-shaped valley carved by the ice and the rocks frozen in it. Deposition by ice: a ridge or heap of mixed, unsorted clay, sand and boulders, or a large boulder (an erratic) sitting far from rock of its own type. Any two of these, correctly labeled, earn full credit.
Question 18 of 20 · Short Answer
Invented data: the marble steps of an old building have worn down 4.5 mm in 300 years. Find the rate per century and predict how long the steps would take to wear down 3 cm.
Rate = 4.5 mm ÷ 3 centuries = 1.5 mm per century (0.015 mm per year). 3 cm = 30 mm, and 30 ÷ 1.5 = 20 centuries, or 2,000 years, if the rate stays the same.
Question 19 of 20 · Short Answer
In the shake test, sugar cubes lose mass and their corners round off. Explain what part of a real river the model represents and give one way the model is not like a real river.
The shaking stands for river water tumbling rock fragments, which knock against each other and the riverbed and lose their sharp corners (weathering during transport). The model is not like a river because it is much faster (minutes instead of years), the cubes are softer than rock, and there is no flowing water carrying the pieces downstream and sorting them by size.
Question 20 of 20 · Short Answer
Invented data: over 100 years a fault moved 3.0 m in total. One earthquake moved it 2.5 m in seconds, and slow creep moved it the rest. What percent of the movement happened in the earthquake? Explain what this shows about how geoscience processes behave.
Percent = 2.5 ÷ 3.0 × 100 ≈ 83%. The fault mostly moves gradually, but most of the total change came from one sudden event, so the process is gradual but punctuated by a catastrophic event.
0 of 20 answered · 0 correct
06
Frequently Asked Questions
10 Questions
What does MS-ESS2-2 mean?
MS-ESS2-2 asks middle school students to construct an explanation, based on evidence, for how geoscience processes have changed Earth's surface at different time and spatial scales. The code means Middle School, Earth and Space Science, core idea 2 (Earth's Systems), performance expectation 2.
Is MS-ESS2-2 taught in grade 6, 7 or 8?
It depends on the school. MS-ESS2-2 is a middle school standard for grades 6-8, and it is often taught in an Earth science unit with MS-ESS2-1 (the rock cycle) and MS-ESS2-3 (plate motions). Some schools pair it with MS-ESS3-2 on natural hazards.
What are examples of geoscience processes in MS-ESS2-2?
The Clarification Statement names surface weathering and deposition by the movements of water, ice and wind. It also mentions slow plate motions, the uplift of mountain ranges, landslides, microscopic chemical reactions, earthquakes, volcanoes and meteor impacts. Any of these can anchor an explanation.
Does MS-ESS2-2 have an assessment boundary?
No. MS-ESS2-2 has no official Assessment Boundary. The Clarification Statement sets the emphasis instead: processes at large and small scales, gradual processes punctuated by catastrophic events, and local geographic features where appropriate.
What does "varying time and spatial scales" mean?
Time scale is how long a change takes, from seconds for a rockfall to millions of years for a mountain range. Spatial scale is how large an area it affects, from a single grain to a whole region. A good explanation states both, because a change can be fast and large, slow and small, or any mix.
What does "gradual but punctuated by catastrophic events" mean?
It means a process usually works slowly but is interrupted now and then by a sudden event that causes a large change. A river may drop a little sediment each year and then lay down a thick layer in one flood. Records that average the years together can hide the sudden events.
What is the difference between weathering, erosion and deposition?
Weathering breaks rock down where it sits, erosion carries the pieces away, and deposition drops them in a new place. Water, ice and wind can do all three. For example, ice can scratch bedrock, carry boulders and drop them in a ridge when it melts.
How do students construct an explanation for MS-ESS2-2?
Use a claim, evidence and reasoning frame. The claim says what process changed the surface; the evidence is data or observations, such as a rate, a layer or a scratch; and the reasoning explains why that evidence points to that process. Ask students to state the time and spatial scale in the reasoning.
How can teachers use local landforms for MS-ESS2-2?
The Clarification Statement says to emphasize processes that shape local geographic features where appropriate. A nearby stream bank, beach, hill, road cut or even weathered building stone works well. Students photograph or sketch it, list evidence and explain which processes shaped it.
What comes after MS-ESS2-2 in high school?
HS-ESS2-1 asks students to model how internal and surface processes build and wear down landforms at different scales, and HS-ESS2-5 asks them to investigate how the properties of water affect Earth materials and surface processes. Both extend the explanations from MS-ESS2-2.
07
Related Standards
6 standards
These standards connect to MS-ESS2-2: prerequisites to review first, parallel standards at the same level, and next steps that build on it.
Before this lesson
4-ESS2-1Prerequisite
Observe or measure the effects of weathering and the rate of erosion
Lesson coming soon
4-ESS1-1Prerequisite
Use patterns in rock layers and fossils to explain changes in a landscape
Lesson coming soon
Alongside
MS-ESS2-1Parallel
Model the cycling of Earth's materials and the energy that drives it
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