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# 2 - MATH

## MATHEMATICS

**Operations and Algebraic Thinking 2.OA**

**A. Represent and solve problems involving addition and subtraction.**

**1. Use addition and subtraction within 100 to solve one- and two-step word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem.**

Student Video - Another Look for Lesson 1-9 Solve Addition and Subtraction Word Problems

Listen and Look Video explaining overview for Lesson 3-8 Solve One-Step and Two-Step Problems

Student Video - Another Look for Lesson 3-8 Solve One-Step and Two-Step Problems

Listen and Look Video explaining overview for Lesson 4-7 Solve One-Step and Two-Step Problems

Student Video - Another Look for Lesson 4-7 Solve One-Step and Two-Step Problems

Listen and Look Video explaining overview for Lesson 5-8 Solve One-Step and Two-Step Problems

Student Video - Another Look for Lesson 5-8 Solve One-Step and Two-Step Problems

Listen and Look Video explaining overview for Lesson 6-8 Solve One-Step and Two-Step Problems

Student Video - Another Look for Lesson 6-8 Solve One-Step and Two-Step Problems

Listen and Look Video explaining overview for Lesson 7-1 Represent Addition and Subtraction Problems

Student Video - Another Look for Lesson 7-1 Represent Addition and Subtraction Problems

Student Video - Another Look for Lesson 7-2 Mixed Practice: Solve Addition and Subtraction Problems

Student Video - Another Look for Lesson 7-3 Continue Practice with Addition and Subtraction Problems

Listen and Look Video explaining overview for Lesson 7-4 Solve Two-Step Problems

Student Video - Another Look for Lesson 7-4 Solve Two-Step Problems

Listen and Look Video explaining overview for Lesson 7-5 Continue to Solve Two-Step Problems

Student Video - Another Look for Lesson 7-5 Continue to Solve Two-Step Problems

Listen and Look Video explaining overview for Lesson 7-6 Math Practices & Problem Solving: Reasoning

Student Video - Another Look for Lesson 7-6 Math Practices & Problem Solving: Reasoning

**B. Add and subtract within 20.**

**2. Fluently add and subtract within 20 using mental strategies.By end of grade 2, know from memory all sums of two single-digit numbers and related differences.**

Listen and Look Video explaining overview for Lesson 1-1 Addition Fact Strategies

Student Video - Another Look for Lesson 1-1 Addition Fact Strategies

Listen and Look Video explaining overview for Lesson 1-2 Doubles and Near Doubles

Student Video - Another Look for Lesson 1-2 Doubles and Near Doubles

Listen and Look Video explaining overview for Lesson 1-3 Make a 10 to Add

Student Video - Another Look for Lesson 1-3 Make a 10 to Add

Listen and Look Video explaining overview for Lesson 1-4 Addition Fact Patterns

Student Video - Another Look for Lesson 1-4 Addition Fact Patterns

Listen and Look Video explaining overview for Lesson 1-5 Count On and Count Back to Subtract

Student Video - Another Look for Lesson 1-5 Count On and Count Back to Subtract

Listen and Look Video explaining overview for Lesson 1-6 Think Addition to Subtract

Student Video - Another Look for Lesson 1-6 Think Addition to Subtract

Listen and Look Video explaining overview for Lesson 1-7 Make a 10 to Subtract

Student Video - Another Look for Lesson 1-7 Make a 10 to Subtract

Listen and Look Video explaining overview for Lesson 1-8 Practice Addition and Subtraction Facts

Student Video - Another Look for Lesson 1-8 Practice Addition and Subtraction Facts

**C. Work with equal groups of objects to gain foundations for multiplication.**

**4. Use addition to find the total number of objects arranged in rectangular arrays with up to five rows and up to five columns; write an equation to express the total as a sum of equal addends.**

Listen and Look Video explaining overview for Lesson 2-3 Use Arrays to Find Totals

Student Video - Another Look for Lesson 2-3 Use Arrays to Find Totals

Listen and Look Video explaining overview for Lesson 2-4 Make Arrays to Find Totals

Student Video - Another Look for Lesson 2-4 Make Arrays to Find Totals

**Number and Operations in Base Ten 2.NBT**

**A. Understand place value.**

**1. Understand that the three digits of a three-digit number represent amounts of hundreds, tens, and ones; e.g., 706 equals 7 hundreds, 0 tens, and 6 ones.Understand the following as special cases:**

Listen and Look Video explaining overview for Lesson 9-2 Models and 3-Digit Numbers

Student Video - Another Look for Lesson 9-2 Models and 3-Digit Numbers

Listen and Look Video explaining overview for Lesson 9-3 Name Place Values

Student Video - Another Look for Lesson 9-3 Name Place Values

**a. 100 can be thought of as a bundle of ten tens—called a “hundred.”**

Listen and Look Video explaining overview for Lesson 9-1 Understand Hundreds

Student Video - Another Look for Lesson 9-1 Understand Hundreds

**b. The numbers 100, 200, 300, 400, 500, 600, 700, 800, 900 refer to one, two, three, four, five, six, seven, eight, or nine hundreds (and 0 tens and 0 ones).**

**2. Count within 1,000; skip-count by 5s, 10s, and 100s. Identify patterns in skip counting starting at any number.**

Listen and Look Video explaining overview for Lesson 9-6 Place-Value Patterns with Numbers

Student Video - Another Look for Lesson 9-6 Place-Value Patterns with Numbers

Listen and Look Video explaining overview for Lesson 9-7 Skip Count by 5's, 10's, and 100's to 1,000

Student Video - Another Look for Lesson 9-7 Skip Count by 5's, 10's, and 100's to 1,000

**3. Read and write numbers to 1,000 using base-ten numerals, number names, and expanded form.**

Listen and Look Video explaining overview for Lesson 9-4 Read and Write 3-Digit Numbers

Student Video - Another Look for Lesson 9-4 Read and Write 3-Digit Numbers

Listen and Look Video explaining overview for Lesson 9-5 Different Ways to Name the Same Number

Student Video - Another Look for Lesson 9-5 Different Ways to Name the Same Number

**B. Use place value understanding and properties of operations to add and subtract.**

**5. Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction.**

Listen and Look Video explaining overview for Lesson 3-1 Add Tens and Ones on a Hundred Chart

Student Video - Another Look for Lesson 3-1 Add Tens and Ones on a Hundred Chart

Listen and Look Video explaining overview for Lesson 3-2 Add Tens on an Open Number Line

Student Video - Another Look for Lesson 3-2 Add Tens on an Open Number Line

Listen and Look Video explaining overview for Lesson 3-3 Add Tens and Ones on an Open Number Line

Student Video - Another Look for Lesson 3-3 Add Tens and Ones on an Open Number Line

Listen and Look Video explaining overview for Lesson 3-4 Break Apart Numbers to Add

Student Video - Another Look for Lesson 3-4 Break Apart Numbers to Add

Listen and Look Video explaining overview for Lesson 3-5 Continue to Break Apart Numbers to Add

Student Video - Another Look for Lesson 3-5 Continue to Break Apart Numbers to Add

Listen and Look Video explaining overview for Lesson 3-6 Add Using Compensation

Student Video - Another Look for Lesson 3-6 Add Using Compensation

Listen and Look Video explaining overview for Lesson 3-7 Practice Adding Using Strategies

Student Video - Another Look for Lesson 3-7 Practice Adding Using Strategies

Listen and Look Video explaining overview for Lesson 4-1 Add with Partial Sums

Student Video - Another Look for Lesson 4-1 Add with Partial Sums

Listen and Look Video explaining overview for Lesson 4-2 Continue to Add with Partial Sums

Student Video - Another Look for Lesson 4-2 Continue to Add with Partial Sums

Listen and Look Video explaining overview for Lesson 4-3 Models to Add 2-Digit Numbers

Student Video - Another Look for Lesson 4-3 Models to Add 2-Digit Numbers

Listen and Look Video explaining overview for Lesson 4-4 Add 2-Digit Numbers

Student Video - Another Look for Lesson 4-4 Add 2-Digit Numbers

Listen and Look Video explaining overview for Lesson 4-6 Practice Adding

Student Video - Another Look for Lesson 4-6 Practice Adding

Listen and Look Video explaining overview for Lesson 5-1 Subtract Tens and Ones on a Hundred Chart

Student Video - Another Look for Lesson 5-1 Subtract Tens and Ones on a Hundred Chart

Student Video - Another Look for Lesson 5-2 Count Back to Subtract on an Open Number Line

Student Video - Another Look for Lesson 5-4 Add Up to Subtract Using an Open Number Line

Listen and Look Video explaining overview for Lesson 5-5 Break Apart Numbers to Subtract

Student Video - Another Look for Lesson 5-5 Break Apart Numbers to Subtract

Listen and Look Video explaining overview for Lesson 5-6 Continue to Break Apart Numbers to Subtract

Student Video - Another Look for Lesson 5-6 Continue to Break Apart Numbers to Subtract

Listen and Look Video explaining overview for Lesson 5-7 Subtract Using Compensation

Student Video - Another Look for Lesson 5-7 Subtract Using Compensation

Listen and Look Video explaining overview for Lesson 6-1 Regroup 1 Ten for 10 Ones

Student Video - Another Look for Lesson 6-1 Regroup 1 Ten for 10 Ones

Student Video - Another Look for Lesson 6-2 Models to Subtract 2-Digit and 1-Digit Numbers

Listen and Look Video explaining overview for Lesson 6-3 Subtract 2-Digit and 1-Digit Numbers

Student Video - Another Look for Lesson 6-3 Subtract 2-Digit and 1-Digit Numbers

Listen and Look Video explaining overview for Lesson 6-4 Models to Subtract 2-Digit Numbers

Student Video - Another Look for Lesson 6-4 Models to Subtract 2-Digit Numbers

Listen and Look Video explaining overview for Lesson 6-5 Subtract 2-Digit Numbers

Student Video - Another Look for Lesson 6-5 Subtract 2-Digit Numbers

Listen and Look Video explaining overview for Lesson 6-6 Use Addition to Check Subtraction

Student Video - Another Look for Lesson 6-6 Use Addition to Check Subtraction

Listen and Look Video explaining overview for Lesson 6-7 Practice Subtracting

Student Video - Another Look for Lesson 6-7 Practice Subtracting

**7. Add and subtract within 1,000, 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. Understand 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.**

Listen and Look Video explaining overview for Lesson 10-2 Add on an Open Number Line

Student Video - Another Look for Lesson 10-2 Add on an Open Number Line

Listen and Look Video explaining overview for Lesson 10-3 Add Using Mental Math

Student Video - Another Look for Lesson 10-3 Add Using Mental Math

Listen and Look Video explaining overview for Lesson 10-4 Add Using Partial Sums

Student Video - Another Look for Lesson 10-4 Add Using Partial Sums

Listen and Look Video explaining overview for Lesson 10-5 Use Models to Add

Student Video - Another Look for Lesson 10-5 Use Models to Add