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From the nonprofit Great Minds A Story of Units ® Understanding the Major Work of the K–2 Grade Band Virtual Engagement Materials March 2021

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From the nonprofit Great Minds

A Story of Units®

Understanding the Major Work of the K–2 Grade Band Virtual Engagement Materials

March 2021

Contents

Part A Materials

Curriculum Map for A Story of Units®, Page 3 Units at Different Grade Levels, Page 4 Level 1: Direct Modeling by Counting All, Page 5 Object Configurations, Page 6 Hands Number Line to 3, Page 7 Personal Reflection, Page 8 Say Ten Counting, Page 9 Level 2: Counting On, Page 10 Simplifying Strategies for Addition, Page 11 Addition Algorithm with the Chip Model, Page 12 Personal Reflection, Page 13

Part B Materials

Level 1: Direct Modeling by Taking Away, Page 14 Level 3: Take from Ten, Page 15 Simplifying Strategies for Subtraction, Page 16 Subtraction with Compensation, Page 17 Subtraction Algorithm with the Chip Model, Page 18 Personal Reflection, Page 19 Applying Strategies to Add and Subtract, Page 20 Personal Reflection, Page 21 Lesson Analysis: Grade 2 Module 5 Lesson 12, Pages 22–27 Lesson Analysis: Grade 2 Module 5 Lesson 18, Pages 28–33 Final Reflection, Page 34

Appendix

Excerpt from Progressions for the Common Core State Standards in Mathematics (draft). Grades K–5, Counting and Cardinality & Operations and Algebraic Thinking, Appendix, Pages 35–38 Sample Solutions to Page 20, Page 39

Works Cited, Page 40

Credits, Page 41

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Virtual Engagement MaterialsUnderstanding the Major Work of the K–2 Grade Band

3

Curriculum Map for A Story of Units®

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Units at Different Grade Levels

Kindergarten

Grade 1

Grade 2

Grade 3

Grade 4

Grade 5

Bananas, frogs, cubes, people Ones

Tens Centimeters Halves, fourths

Hundreds Meters, inches, feet Thirds

Twos, threes, fours, fives, sixes, sevens, eights, nines Grams, kilograms, liters Square meters, square feet Sixths, eighths

Thousands, ten thousands, hundred thousands Mixed units (e.g., 1 pound 8 ounces, 5 feet 6 inches, 4 liters 350 milliliters) Tenths, twelfths, hundredths

Millions, thousandths Any denominator Cubic meters, cubic feet

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Level 1: Counting All

Directions: Define each of the four components of the Number Core listed below.

1. Number word list

2. 1 : 1 correspondence

3. Cardinality

4. Written number symbols

Virtual Engagement MaterialsUnderstanding the Major Work of the K–2 Grade Band

For more information on Level 1: Counting All, see appendix A.

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Object Configurations in Kindergarten

Kindergarten Module 1, Lesson 7

Kindergarten Module, 1 Lesson 8

Kindergarten Module 1, Lesson 10

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Counting the Math Way (GK M1 L2) Materials: (S) Left-hand mat (Lesson 1 Fluency Template), bag of beans or small counters

T: How many hands do you see on your mat? S: 1. T: How many real hands do you have? S: 2. T: Put 1 of your real hands down on the mat so that it matches the picture of the hand on your mat exactly.

Make sure to line up all your fingers. T: Take 1 bean out of your bag, and put it on the pinky fingernail on your mat. How many fingers have a bean? S: 1. T: Which finger is it? S: Pinky. T: Show me your real pinky finger. This is the finger we’ll start counting with.

(Demonstrate.) S: 1. (Hold up the pinky finger of the left hand, palm facing away from students.) T: Put another bean on the very next finger. How many fingers have beans on them now? S: 2. T: Show me which fingers have beans. Use your mat to help you. (Circulate and support.)

Let’s count on fingers from 1 to 2. Ready? S: 1 (hold up the pinky finger of the left hand), 2 (hold up pinky and ring finger, palm

out). T: Put another bean on the very next finger. How many fingers have beans on them now? S: 3. T: Show me which fingers have beans. Use your mat to help you. (Circulate and support.)

Let’s count on fingers from 1 to 3. Ready? S: 1 (hold up the pinky finger of the left hand), 2 (hold up pinky and ring finger, palm

out), 3 (hold up pinky, ring finger, and middle finger, palm out). T: Very good! See if you can do it without looking at the mat. Close it up (show closed

fist). Ready? S: 1, 2, 3 (show fingers). T: Stay here at 3. Now, count back down to 1. Ready? S: 3, 2, 1.

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Personal Reflection

How do foundational understandings of numbers and place value support students in developing understanding of addition and subtraction?

8

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Say Ten Counting

1 2 3 4 5 6 7 8 9 10

one two three four five six seven eight nine ten

yi er san si wu liu qi ba jiu shi

Directions: Write the numbers 13 through 20 in Chinese.

13: ________________

14: ________________

15: ________________

16: ________________

17: ________________

18: ________________

19: ________________

20: ________________

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Level 2: Counting On

Directions: Round1 Ma e a the number bonds o 𝟖 seen in the pictureRound2 Use one number card and one dot card to sho 𝟐 parts Count on rom 𝟏 addend

or more in ormation on e e 2 Counting n, see appendi

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ȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤȤτ bears ent to p ay Some more bears came hen there ere χ bears p aying o many bears came to p ay

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a. Number bond: b. Arrow way:

2. Directions: Solve the following problems, and use 48 + 20 to help you.

a. 48 + 21

b. 48 + 19

48 + 20

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Simplifying Strategies for Addition

1. Directions: Solve by using a number bond and the arrow way.

Jot your thoughts!

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Addition Algorithm with the Chip Model

Directions: Solve vertically. Draw chips on the place value chart and bundle when needed.

76 + 27

hundreds tens ones

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Personal Reflection

Why is it important that students gain an understanding of and skill with a variety of strategies? Why are these so powerful for building understanding of addition?

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Lesson 22: Decompose the number 6 using 5-group drawings by breaking off or removing a part, and record each decomposition with a drawing and subtraction equation.

Lesson 22 Problem Set K 4

Name Date

Fill in the number bonds.

Cross out 1 hat.

6 – 1 = 5

Cross out 5 snowflakes.

6 - 5 = 1

Cross out 2 snowflakes.

6 - 2 = 4

6

6

6

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Level 1: Counting All to Take Away

Level 3: Take from Ten

12 − 8

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Simplifying Strategies for Subtraction

1. Directions: Solve by using a number bond and the arrow way.

56 − 20

a. Number bond: b. Arrow way:

2. Directions: Solve the following problems using 56 − 20 to help you.

a. 56 − 21

b. 56 − 19

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Using Compensation to Subtract

Directions: Use the compensation method to subtract. Model your thinking by using tape diagrams.

1. 56 − 19 = _______________ = ______

2. 23 − 9 = _______________ = ______

3. 50 − 29 = _______________ = ______

4. 405 − 199 = _______________ = ______ (Hint: You will not need to rename!)

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Subtraction Algorithm with the Chip Model

Directions: Solve vertically. Draw chips on the place value chart and unbundle when needed.

31 − 18

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Personal Reflection

How do higher-level strategies deepen students’ understanding of subtraction?

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Applying Strategies to Add and Subtract

Directions: Apply the thinking involved in the make ten and take from ten strategies to solve.

4,298 + 27 1,998 + 1,042 1,057 − 49 40,000 − 998

Extend your thinking! Solve by making or taking from a unit.

745 +

45 5.9 + 0.8 5

14 −

34 5.3 − 0.7

Challenge: Use the compensation method to solve the subtraction problems.

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Personal Reflection

How does proficiency with the work of Kindergarten through Grade 2 give students access to specific concepts in later grades?

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Application—Lesson Analysis

Directions:

1. Solve the problem shown.2. Craft an exemplar response to the Student Debrief question below.3. Highlight language in the Concept Development on the following pages that will activate

student thinking about the understandings included in your response.

Grade 2 Module 5 Lesson 12

Problem 2(c): Choose the best strategy to solve. Explain why you chose that strategy.

378 + 464

Student Debrief: How did you solve Problem 2(c)? What made 2(c) more difficult to solve with a simplifying strategy? Could you have done so?

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Lesson 12 2 5

Lesson 12: Choose and explain solution strategies and record with a written addition method.

Lesson 12 Objective: Choose and explain solution strategies and record with a written addition method.

Suggested Lesson Structure

Fluency Practice (12 minutes)

Concept Development (38 minutes)

Student Debrief (10 minutes)

Total Time (60 minutes)

Fluency Practice (12 minutes)

Compensation 2.NBT.7 (4 minutes) Sprint: Compensation Addition 2.NBT.7 (8 minutes)

Compensation (4 minutes)

Note: This fluency activity reviews compensation, the mental math strategy. By making a multiple of 10, students solve a much simpler addition problem. Draw a number bond for the first problem on the board to help students visualize the decomposition.

T: (Write 61 + 99 = _____.) Let’s use a mental math strategy to add.

How much more does 99 need to make 100? S: 1 more. T: Where can 99 get 1 more? S: From the 61. T: Take 1 from 61, and give it to 99. Say the simplified

number sentence with the answer. S: 60 + 100 = 160. T: 99 + 46. Say the simplified number sentence with the answer. S: 100 + 45 = 145.

Continue with the following possible sequence: 99 + 38, 98 + 56, 47 + 98, 26 + 98, 54 + 99, 54 + 199, and 73 + 199.

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Lesson 12 2 5

Lesson 12: Choose and explain solution strategies and record with a written addition method.

Sprint: Compensation Addition (8 minutes)

Materials: (S) Compensation Addition Sprint

Note: Students review compensation when adding to gain automaticity.

Concept Development (38 minutes)

Materials: (S) Place value disks (9 hundreds, 18 tens, 18 ones), personal white board

Note: The following lesson is designed to help facilitate a discussion about choosing the most efficient problem-solving strategies. Based on student needs and class ability, strategies other than those listed below may be used to solve. To allow for this in-depth discussion, the Application Problem has been omitted from today’s lesson.

Problem 1: 374 + 210

T: Turn and talk: What are some strategies you could use to solve this problem? S: I can use mental math and place value strategies. I can use the algorithm without place value

disks. I can use arrow notation.

Instruct students to choose a written strategy that they prefer and find most efficient. Encourage students to solve independently, and circulate to provide support. Then, invite a few students to share their work and explain how they applied the specific solution strategy. Remind students who used the algorithm to keep explanations brief.

S1: I used mental math and what I know about place value. I started at 374, and then in my head, I counted on 2 more hundreds to make 574. Then, I added a ten, and I had 584.

S2: I wrote the problem vertically and added ones, then tens, then hundreds under the line. It was easy to use the algorithm; I didn’t even need to make a new ten or hundred.

S3: I used arrow notation to show the change as I added. I started with 374 and added 200, so I drew an arrow to 574. Then, I added on 10 more and drew an arrow to 584.

T: Turn and talk: Now that you’ve heard different solution strategies, which method do you prefer for this problem and why?

S: I like the arrow way best because 210 only has hundreds and tens, so it is easy to break apart and add on. The chip model and place value disks take longer than using the arrow way. Plus, we don’t have to bundle in this problem. Now that we understand place value, it’s easy to solve mentally.

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dharm
Cross-Out
dharm
Inserted Text
2021

Lesson 12 2 5

Lesson 12: Choose and explain solution strategies and record with a written addition method.

T: I’m noticing that nobody suggested a number bond for this problem. Why not? S: None of the numbers are close to making the next hundred. It’s too hard to

think of adding on to 374 to make 400. I would have used a number bond if 374 had been 394.

T: I like the way you’re thinking! Let’s take a look at another problem.

Problem 2: 398 + 142

T: Turn and talk: What are some strategies you could use to solve this problem? S: Place value disks and the vertical form. A number bond. Arrow notation.

Again, instruct students to choose a written strategy that they prefer and find most efficient. Encourage them to solve independently, and circulate to provide support. Then, invite a few different students to share their work and explain how they applied the specific solution strategy. Again, remind students who used the written addition to keep explanations brief.

S1: I counted the place value disks to show both parts. I started by adding my ones. When I made a ten, I exchanged 10 ones for 1 ten. Then, I added my tens. When I made a hundred, I exchanged 10 tens for a hundred. Then, I added my hundreds. The answer is 540.

S2: I know that 398 is very close to 400, so I used a number bond. I decomposed 142 into 140 and 2. Then, I bonded the 2 with 398 to make 400, and 400 plus 140 equals 540.

S3: I like arrow notation because you can start with 398 and first add 2, so 400, then add 100, then 40 more, and you have 540.

T: Turn and talk: Which method do you think is best for this problem and why?

S: Making a hundred is the easiest and quickest, especially since you only needed to add on 2. Using the chip model is good, but it was faster to break apart the 142. I prefer the arrow way because once you add 2 to make 400, it’s easy to add a hundred and 4 tens.

Problem 3: 287 + 234

Note: For this problem, some students may choose to represent the problem using place value disks or drawings, while others may choose to solve using vertical form. Although the most efficient strategy will most likely be using vertical form, the Grade 2 expectation is not that students use the algorithm alone but that they use it in conjunction with a representation.

T: Turn and talk: What are some strategies you could use to solve this problem? S: A place value disk drawing. I would write just using the vertical form.

Students follow the same procedure as suggested in Problems 1 and 2. Since this problem does not lend itself to other simplifying strategies, invite one student, or maybe two, to share.

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Lesson 12 2 5

Lesson 12: Choose and explain solution strategies and record with a written addition method.

NOTES ON MULTIPLE MEANS OF REPRESENTATION:

During the Debrief, invite students to share exemplary explanations with the whole class. Encourage students to model alternative, even creative, solutions. For example, for Problem 1 on the Problem Set (299 + 399), a student might suggest adding hundreds and then subtracting 2: “If you add 1 to 299 and 399, you get 300 + 400 equals 700. Then, you have to subtract 2 from 700, so 698.”

NOTES ON MULTIPLE MEANS OF ENGAGEMENT:

Writing about math can be daunting for some students. Provide oral options for informal

assessment on the Problem Setrather than writing.

Before they begin writing, askstudents questions to probe.

Support written responses on theProblem Set by providing a startersuch as, “The number bond was the best strategy because …”

S: My model shows that 11 ones becomes 1 ten 1 one. I showed that by writing 1 on the line below the tens place. 11 tens plus 1 ten is 12 tens, so I showed a new hundred, and then I wrote a 1 on the line below the hundreds place and a 2 below the line in the tens place. Then, I just added my hundred. So, the answer is 521.

T: How was this the most efficient way to solve this problem? Why didn’t you choose a simplifying strategy?

S: Because solving using the arrow way would be too complicated. The make a hundred strategy doesn’t make it easier because the numbers are too far from the closest hundred. Since you have to bundle twice, I like using the chips and the algorithm.

T: Now, you’re going to have the chance to analyze some student work and solve some problems by choosing a written strategy that works best for you.

Problem Set (10 minutes)

Students should do their personal best to complete the Problem Set within the allotted 10 minutes. For some classes, it may be appropriate to modify the assignment by specifying which problems they work on first. Some problems do not specify a method for solving. Students should solve these problems using the RDW approach used for Application Problems.

Student Debrief (10 minutes)

Lesson Objective: Choose and explain solution strategies and record with a written addition method.

The Student Debrief is intended to invite reflection and active processing of the total lesson experience.

Invite students to review their solutions for the Problem Set. They should check work by comparing answers with a partner before going over answers as a class. Look for misconceptions or misunderstandings that can be addressed in the Student Debrief. Guide students in a conversation to debrief the Problem Set and process the lesson.

Any combination of the questions below may be used to lead the discussion.

Share with your partner: For Problem 1, which strategy was most efficient for Tracy to use? Why?Do you agree or disagree with your partner?

Can you explain any alternate problem-solving strategies for Problem 1?

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Lesson 12 2 5

Lesson 12: Choose and explain solution strategies and record with a written addition method.

To solve Problem 2(a), which strategy did youchoose? Why?

To solve Problem 2(b), which strategy did youchoose? How did your understanding of placevalue help you solve this problem quickly?

How did you solve Problem 2(c)? What made2(c) more difficult to solve with a simplifyingstrategy? Could you have done so?

Exit Ticket (3 minutes)

After the Student Debrief, instruct students to complete the Exit Ticket. A review of their work will help with assessing students’ understanding of the concepts that were presented in today’s lesson and planning more effectively for future lessons. The questions may be read aloud to the students.

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Application—Lesson Analysis

Directions:

1. Solve the problem shown.2. Craft an exemplar response to the Student Debrief question below.3. Highlight language in the Concept Development on the following pages that will activate

student thinking about the understandings included in your response.

Grade 2 Module 5 Lesson 18

Problem 3(b): Choose the best strategy to solve. Explain why you chose that strategy.

808 − 597

Student Debrief: For Problem 3(b), 808 − 597, how did you rename 808 for subtraction? What does that look like using vertical form? Or, why did you choose to solve mentally?

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Lesson 18: Apply and explain alternate methods for subtracting from multiples of 100 and from numbers with zero in the tens place.

Lesson 18 2 5

NOTES ON MULTIPLE MEANS OF ACTION AND EXPRESSION:

Initially adjust numbers in the calculation so that students can see that they need to add rather than subtract, as the word fewer suggests.

Try replacing the two-digit numbers with single-digit numbers to emphasize the relationships. For example, Joseph collected six golf balls from the course. He still had three fewer than his friend. With smaller, more manageable numbers, students can use one-to-one matching to make sense of this comparison problem type.

Use concrete materials to model the second part for students who still struggle to grasp the concept.

Lesson 18 Objective: Apply and explain alternate methods for subtracting from multiples of 100 and from numbers with zero in the tens place.

Suggested Lesson Structure

Application Problem (8 minutes) Fluency Practice (10 minutes)

Concept Development (32 minutes)

Student Debrief (10 minutes)

Total Time (60 minutes)

Application Problem (8 minutes)

Joseph collected 49 golf balls from the course. He still had 38 fewer than his friend Ethan.

a. How many golf balls did Ethan have?

b. If Ethan gave Joseph 24 golf balls, who had more golf balls? How many more?

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Lesson 18: Apply and explain alternate methods for subtracting from multiples of 100 and from numbers with zero in the tens place.

Lesson 18 2 5

Note: In addition to the compare bigger unknown component of Lesson 17’s Application Problem, this problem requires students to shift quantities from one boy to the other (24 from Joseph to Ethan) and then to find the difference. In this case, drawing a tape diagram highlights the shifting quantities and enables students to visualize the more complex processes. Lead students in the RDW process, or encourage them to work together to solve and check their work.

Fluency Practice (10 minutes)

Grade 2 Core Fluency Practice Sets 2.OA.2 (5 minutes) Get the Ten Out and Subtract 2.NBT.5 (5 minutes)

Grade 2 Core Fluency Practice Sets (5 minutes)

Materials: (S) Grade 2 Core Fluency Practice Sets (Lesson 14 Core Fluency Practice Sets)

Note: During Topic C and for the remainder of the year, each day’s fluency activity includes an opportunity for review and mastery of the sums and differences with totals through 20 by means of the Core Fluency Practice Sets or Sprints. In Lesson 14, Practice Sets are provided, and the process is explained in detail.

Get the Ten Out and Subtract (5 minutes)

Note: Students practice taking out the ten and subtracting to prepare for unbundling a ten in today’s lesson.

T: For every expression I give, subtract the ones from ten. When I say 12 – 4, you say 10 – 4 = 6. Ready?

T: 12 – 4. S: 10 – 4 = 6. T: 13 – 7. S: 10 – 7 = 3.

Practice taking the ten out of expressions fluently before adding the ones back.

T: Now, let’s add back the ones. T: 12 – 4. Take from ten. S: 10 – 4 = 6. T: Now, add back the ones. S: 6 + 2 = 8.

Continue with the following possible sequence: 13 – 7, 11 – 8, 13 – 9, 15 – 7, and 14 – 8.

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Lesson 18: Apply and explain alternate methods for subtracting from multiples of 100 and from numbers with zero in the tens place.

Lesson 18 2 5

Concept Development (32 minutes)

Materials: (S) Personal white board

Problem 1: Use compensation to solve 300 – 159.

T: (Write 300 – 159 on the board.) We know we can use vertical form to subtract from the hundred. Is this something we can do quickly?

S: No, because we have to decompose numbers. No, we have to unbundle twice to subtract.

T: I’m going to show you a more efficient way to subtract. T: (Draw the tape diagram to the right on the board.) What happens if

I take one off each number? What is my new subtraction problem? S: 299 – 158. T: (Draw a new tape diagram showing the compensation.) T: Is this any easier to solve? Turn and talk with a partner. S: Yes! There’s no renaming. Now, we’re ready to subtract in all

place values! T: Solve this problem, and turn your personal white board over when

you are finished. T: What is 299 – 158? S: 141.T: Is this similar to a strategy you’ve used before? Talk with a partner. S: It’s like when we added the same number to both numbers. Yes, like with those other tape

diagrams where they both got bigger by the same amount. I think it was called compensation.

Problem 2: Add to solve 400 – 278.

T: (Write 400 – 278 on the board.) Let’s try a different way to subtract from the hundred. Can we use a different operation to solve?

S: Yes, we can start with 278 and count up to 400. We can start with 278, which is one part, and use the arrow way to show the other part. 400 minus 278 is like 278 plus something equals 400.

T: (Draw a number bond with these numbers on the board.) T: (Write 278 + ____ = 400.) Why can I write the problem like this? Talk with a

partner. S: Because 400 is the whole, and we know one part. Part plus part makes whole. We don’t know

one of the parts, so we make it a blank. T: Let’s use the arrow way to solve this problem. (Write

278 → on the board.) How many more do we need to make the next ten?

S: 2.

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Lesson 18: Apply and explain alternate methods for subtracting from multiples of 100 and from numbers with zero in the tens place.

Lesson 18 2 5

NOTES ON MULTIPLE MEANS OF REPRESENTATION:

There is no right answer as to which strategy is the best or most efficient for a given problem type. Different students may find certain strategies easier than others. Allow for creativity in modeling, expressing, and critiquing different solution strategies; however, acknowledge that some students may feel most comfortable and capable using a particular method.

T: (Write 2 above the arrow, then 280.) T: How many more do we need now to get to the next hundred? (Record student responses.) S: 20. 2 tens.T: How many more do we need to get to our whole? S: 100.T: We wrote 2, then 20, then 100. Put them altogether, and what do we get? S: 122.T: So, 400 – 278 is …? S: 122.

Problem 3: 605 – 498

T: Now, let’s subtract from a number with a zero in the tens place. Which strategies could we use to solve this problem?

S: We could use the arrow way to solve it with addition because it’s easy to make 500 and then get to 605. We could take 6 off both numbers to make 599 – 492, which means we don’t have to do any renaming. We could just use vertical form.

Take students through the process of solving the problem by relating the chip model to vertical form, renaming 605 as 5 hundreds, 9 tens, 15 ones in one step. When finished, engage students in a discussion about which methods they prefer.

Instruct students to work in pairs through the following problems, discussing which strategy they think would work best for each problem: 500 – 257, 702 – 195, and 600 – 314. As students demonstrate proficiency renaming in one step, instruct them to work on the Problem Set.

Problem Set (10 minutes)

Students should do their personal best to complete the Problem Set within the allotted 10 minutes. For some classes, it may be appropriate to modify the assignment by specifying which problems they work on first. Some problems do not specify a method for solving. Students should solve these problems using the RDW approach used for Application Problems.

Student Debrief (10 minutes)

Lesson Objective: Apply and explain alternate methods for subtracting from multiples of 100 and from numbers with zero in the tens place.

The Student Debrief is intended to invite reflection and active processing of the total lesson experience.

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Lesson 18: Apply and explain alternate methods for subtracting from multiples of 100 and from numbers with zero in the tens place.

Lesson 18 2 5

Invite students to review their solutions for the Problem Set. They should check work by comparing answers with a partner before going over answers as a class. Look for misconceptions or misunderstandings that can be addressed in the Student Debrief. Guide students in a conversation to debrief the Problem Set and process the lesson.

Any combination of the questions below may be used to lead the discussion.

For Problem 1, how did you use the arrow way tosolve? What did you add on first to efficientlysolve each problem? Why?

For Problem 2, explain the meaning of the 9 inthe tens place. Where is the other ten?

For Problem 3(a), 600 – 437, explain the strategyyou chose to solve. Why was using the arrowway easier than subtracting using the algorithm?

For Problem 3(b), 808 – 597, how did you rename808 for subtraction? What does that look likeusing vertical form? Or, why did you choose tosolve mentally?

For Problem 4, how does the smiling student usecompensation to make the subtraction problemmuch simpler? Why is this strategy a good choicehere?

How did you use compensation to solve Problem5(a) and (b)? What other simplifying strategiescould you have used to solve? Which do youprefer?

Exit Ticket (3 minutes)

After the Student Debrief, instruct students to complete the Exit Ticket. A review of their work will help with assessing students’ understanding of the concepts that were presented in today’s lesson and planning more effectively for future lessons. The questions may be read aloud to the students.

A STORY OF UNITS

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Final Reflection

How will understanding the major work of the K–2 grade band help you address your students' unfinished learning and ensure they can all access grade-level content in your classroom?

Based on our work today, what will you start doing, what you will keep doing, and what you will stop doing when you plan for instruction and teach your students?

Virtual Engagement MaterialsUnderstanding the Major Work of the K–2 Grade Band

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Appendix: Counting and Cardinality and Operations and Algebraic Thinking Appendix1

1 Common Core Standards Writing Team. (2011, May 29). Progressions for the Common Core State Standards in Mathematics (draft). Grades K–5, Counting and Cardinality & Operations and Algebraic Thinking. Tucson, AZ: Institute for Mathematics and Education, University of Arizona. https://commoncoretools.files.wordpress.com/2011/05/ccss_progression_cc_oa_k5_2011_05_302.pdf.

Virtual Engagement MaterialsUnderstanding the Major Work of the K–2 Grade Band

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Virtual Engagement MaterialsUnderstanding the Major Work of the K–2 Grade Band

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Virtual Engagement MaterialsUnderstanding the Major Work of the K–2 Grade Band

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Virtual Engagement MaterialsUnderstanding the Major Work of the K–2 Grade Band

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Works Cited

Common Core Standards Writing Team. 2011, May 29. Progressions for the Common Core State Standards in Mathematics (draft). Grades K–5, Counting and Cardinality & Operations and Algebraic Thinking. Tucson, AZ: Institute for Mathematics and Education, University of Arizona. https://commoncoretools.files.wordpress.com/2011/05/ccss_progression_cc_oa_k5_2011_05_302.pdf.

Virtual Engagement MaterialsUnderstanding the Major Work of the K–2 Grade Band

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Credits

Great Minds. 2015. Eureka Math. Washington, DC: Great Minds. https://greatminds.org/math.

Great Minds® has made every effort to obtain permission for the reprinting of all copyrighted material. If any owner of copyrighted material is not acknowledged herein, please contact Great Minds for proper acknowledgment in all future editions and reprints of this handout.

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