# ALEX Classroom Resource

## Grade 2 Mathematics Module 4, Topic D

Classroom Resource Information

Title:

Grade 2 Mathematics Module 4, Topic D

URL:

Content Source:

EngageNY
Type: Lesson/Unit Plan

Overview:

In Lesson 17 of Module 4, Topic D, students extend the base ten understanding developed in Topic A to numbers within 200. Having worked with manipulatives to compose 10 ones as 1 ten, students relate this to composing 10 tens as 1 hundred. For example, students might solve 50 + 80 by thinking 5 ones + 8 ones = 13 ones, so 5 tens + 8 tens = 13 tens = 130. They use place value language to explain when they make a new hundred. They also relate 100 more from Module 3 to + 100 and mentally add 100 to given numbers. In Lesson 18, students use number disks on a place value chart to represent additions with the composition of 1 ten and 1 hundred. They use place value language to explain when they make a new ten and a new hundred, as well as where to show each new unit on the place value chart. In Lesson 19, students relate manipulatives to a written method, recording compositions as new groups below in vertical form. As they did in Topic B, students use place value language to express the action as they physically make 1 hundred with 10 tens disks and 1 ten with 10 ones disks. Working in partners, one student records each change in the written method step by step as the other partner moves the manipulatives. In Lessons 20 and 21, students move from concrete to pictorial as they use math drawings to represent compositions of 1 ten and 1 hundred. Some students may need the continued support of place value drawings with labeled disks, while others use the chip model. In both cases, students relate their drawings to a written method, recording each change they make to their model on the numerical representation. They use place value language to explain these changes. Lesson 22 focuses on adding up to four two-digit addends with totals within 200. Students now have multiple strategies for composing and decomposing numbers, and they use properties of operations (i.e., the associative property) to add numbers in an order that is easiest to compute. For example, when solving 24 + 36 + 55, when adding the ones, a student may make a ten first with 4 and 6. Another student may decompose the 6 to make 3 fives (by adding 1 to the 4).

Content Standard(s):
 Mathematics MA2019 (2019) Grade: 2 11. Use a variety of strategies to add up to four two-digit numbers. Unpacked Content Evidence Of Student Attainment:Students: add up to four 2-digit numbers using strategies based on place value and/or properties of operations. justify solutions and explain the reasoning for the strategy chosen. Teacher Vocabulary:Properties of operationsKnowledge:Students know: to use place value strategies to add up tp four 2-digit numbers and justify their thinking.Skills:Students are able to: strategically choose and then record methods for efficiently and accurately solving addition problems with multiple addends.Understanding:Students understand that: choosing efficient strategies for finding sums of multiple addends depends on the numbers in the problem.Diverse Learning Needs: Essential Skills:Learning Objectives: M.2.11.1: Add within 100, including adding a two-digit number and a one-digit number and adding two two-digit numbers, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method, and explain the reasoning used. M.2.11.2: Add within 20, demonstrating fluency for addition within 10. Use strategies such as counting on; making ten; decomposing a number leading to a ten; and creating equivalent but easier or known sums. M.2.11.3: Determine the value of the number in the ones, tens and hundreds place. M.2.11.4: Model written method for recording horizontal and vertical addition problems. M.2.11.5: Understand that the two digits of a two-digit number represent amounts of tens and ones. M.2.11.6: Match the number in the ones and tens position to a pictorial representation or manipulative of the value. Prior Knowledge Skills: Subtract one from a set of objects (up to 10 objects). Given a group of objects (20 or less), divide the group into smaller groups in various ways. Take away objects from a large group to create two smaller groups. Establish one-to-one correspondence between numbers and objects when given a picture a drawing or objects. Understand number words. Understand that 10 1's = 10. Count backwards from 100 by tens. Mimic counting to 100 by tens. Recognize numbers from 1-100. Understand the concept of size and amount. Understand that the last number name tells the number of objects counted. Understand that 10 1's = 10. Understand that 10 (tens) = 100. Pair a group of objects with a number representing the total number of objects in the group. Alabama Alternate Achievement Standards AAS Standard: M.AAS.2.10 Using vocalization, sign language, augmentative communication, or assistive technology, identify the meaning of the + sign (add, plus, put together) and the sign (subtract, take away, take from) and the = sign (equal, the same as); compose and decompose numbers up to 20 using objects, pictures, drawings, or numbers. Mathematics MA2019 (2019) Grade: 2 12. Add and subtract within 1000 using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method. a. Explain that in adding or subtracting three-digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds. Unpacked Content Evidence Of Student Attainment:Students: add and subtract within 1000. explain their reasoning using concrete models or drawings, or using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction. relate the strategy used to a written method (symbolic and numeric recording of the steps used).Teacher Vocabulary:Compose Decompose Knowledge:Students know: how to count to 1,000. how to identify hundreds, tens, and ones. how to compose numbers. how to decompose two digit numbers. how to record strategies for solving addition and subtraction problems. Skills:Students are able to: add and subtract within 1000. model addition problems using visual models. record strategies for solving addition problems. communicate the relationship between models and symbolic (numeric) representations.Understanding:Students understand that: relationships between models of addition/subtraction problems and written strategies of those models can be used to justify solutions.Diverse Learning Needs: Essential Skills:Learning Objectives: M.2.12.1: Define regrouping, total, sum, difference and solve. M.2.12.2: Add and subtract two two-digit numbers with and without regrouping. M.2.12.3: Determine the value of the number in the ones, tens, hundreds and thousands place using concrete models or drawings and strategies based on place value. M.2.12.4: Match the number in the ones, tens, hundreds and thousands position to a pictorial representation or manipulative of the value. M.2.12.5: Model written method for recording horizontal and vertical addition and subtraction problems. M.2.12.6: Represent two- and three-digit numbers with multiple models. Examples: models—base ten blocks, number lines, linking cubes, straw bundles. M.2.12.7: Recall single-digit addition and subtraction facts. M.2.12.8: Add and subtract within 20, e.g., by using objects or drawings to represent the problem. Prior Knowledge Skills:Notice same/different and some/all. Recognize numerals from 1-50. Add one to a set of objects (up to 10 objects). Given small groups of objects, create larger groups by combining the small groups. Understand ten and 1 (ten 1's =10). Put together two small groups of objects to create a larger group. Subtract one from a set of objects (up to 10 objects). Given a group of objects (20 or less), divide the group into smaller groups in various ways. Take away objects from a large group to create two smaller groups. Understand number words. Establish one-to-one correspondence between numbers and objects when given a picture a drawing or objects. Rote count to 10. Understand amount words, such as more, less, and another. Begin to understand that parts of an object can make a whole. Alabama Alternate Achievement Standards AAS Standard: M.AAS.2.10 Using vocalization, sign language, augmentative communication, or assistive technology, identify the meaning of the + sign (add, plus, put together) and the sign (subtract, take away, take from) and the = sign (equal, the same as); compose and decompose numbers up to 20 using objects, pictures, drawings, or numbers. Mathematics MA2019 (2019) Grade: 2 13. Mentally add and subtract 10 or 100 to a given number between 100 and 900. Unpacked Content Evidence Of Student Attainment:Students: Use a variety of materials and strategies to add or subtract 10 or 100 from a three-digit number in the range of 100 to 900.Knowledge:Students know: use place value models for adding and subtracting numbers from 1 to 1000. use strategies for mentally adding and subtracting multiples of 10 and 100.Skills:Students are able to: use patterns and regularity in counting sequences and understandings of place value to add or subtract a "ten" or a "hundred". communicate reasoning and solution strategies.Understanding:Students understand that: the digits of a 3-digit number represent amounts of hundreds, tens and ones. patterns in the place value system can be used to mentally compute sums and differences.Diverse Learning Needs: Essential Skills:Learning Objectives: M. 2.13.1: Demonstrate conceptual understanding of adding or subtracting 10 using concrete models. M.2.13.2: Recognize the place value of ones, tens and hundreds. M.2.13.3: Count forward and backward by 100. M.2.13.4: Count forward and backward by 10. M.2.13.5: Recall single-digit subtraction facts. M.2.13.6: Recall single-digit addition facts. Prior Knowledge Skills:Recognize numerals from 1-50. Become interested in how many objects she/he has. Understand the concept of size and amount. Given a set number of objects one through ten, answer the question "how many?" Pair the number of objects counted with "how many?" Understand that the last number name tells the number of objects counted. Understand that 10 1's = 10. Establish one-to-one correspondence between numbers and objects when given a picture, a drawing or objects. Pair a group of objects with a number representing the total number of objects in the group. Count objects one-by-one using only one number per object. Recognize that numbers and numerals have meaning. Mimic counting forward and backward by 100. Mimic counting forward and backward by 10. Communicate number words. Recognize after. Recognize before. Understand one less than a number 2 through 20. Understand one more than a number 1 through 20.
Tags: add, addition, mental math, operations, place value, subtract, subtraction, threedigit, twodigit