# All Lessons

### Use Fact Families

(D) Apply basic fact strategies to add and subtract within 20, including making 10 and decomposing a number leading to a 10

1.5.G(G) Apply properties of operations to add and subtract two or three numbers.

1.OA.3 Apply properties of operations as strategies to add and subtract. Examples: If 8 + 3 = 11 is known, then 3 + 8 = 11 is also known. (Commutative property of addition.) To add 2 + 6 + 4, the second two numbers can be added to make a ten, so 2 + 6 + 4 = 2 + 10 = 12. (Associative property of addition.)

1.OA.41.OA.4 Understand subtraction as an unknown-addend problem. For example, subtract 10 - 8 by finding the number that makes 10 when added to 8.

2.OA.22.OA.2 Fluently add and subtract within 20 using mental strategies. By end of Grade 2, know from memory all sums of two one-digit numbers.

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### Memorize Subtraction Facts

(D) Apply basic fact strategies to add and subtract within 20, including making 10 and decomposing a number leading to a 10

1.3.E(E) Explain strategies used to solve addition and subtraction problems up to 20 using spoken words, objects, pictorial models, and number sentences

1.OA.6 Add and subtract within 20, demonstrating fluency for addition and subtraction within 10. Use strategies such as counting on; making ten (e.g., 8 + 6 = 8 + 2 + 4 = 10 + 4 = 14); decomposing a number leading to a ten (e.g., 13 - 4 = 13 - 3 - 1 = 10 - 1 = 9); using the relationship between addition and subtraction (e.g., knowing that 8 + 4 = 12, one knows 12 - 8 = 4); and creating equivalent but easier or known sums (e.g., adding 6 + 7 by creating the known equivalent 6 + 6 + 1 = 12 + 1 = 13).

2.OA.22.OA.2 Fluently add and subtract within 20 using mental strategies. By end of Grade 2, know from memory all sums of two one-digit numbers.

This operations and algebraic thinking lesson covers how to memorize subtraction facts. The lesson includes research-based strategies and strategic questions that prepare students for assessments. In this lesson, students will practice the subtraction facts of numbers 2 through 10 by a combination of reading aloud and writing each fact many times in horizontal and vertical formats.

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### Solve Addition Equations

This algebra and functions lesson focuses on writing addition number sentences. The lesson includes research-based strategies and questions that help prepare students for assessments. In this lesson, students read the word problem and identify addition key words and number words. Then, they write an addition number sentence and practice reading aloud. In addition to the lesson, there are four pages of Independent Practice and review with questions modeled after current adaptive testing items.

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### Write Subtraction Equations

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### Use the Equal Sign

This algebra and functions lesson focuses on using the equal sign. The lesson includes research-based strategies and questions that help prepare students for assessments. In this lesson, students read the problem and complete the math fact. Then, they determine whether the two numbers are equal or not equal using the appropriate symbols. Finally, students interpret the answer using the math fact. In addition to the lesson, there are four pages of equal sign flash cards and eight pages of Independent Practice and review with questions modeled after current adaptive testing items.

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### Create Story Problems (Addition & Subtraction)

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### Memorize Addition Facts

(D) Apply basic fact strategies to add and subtract within 20, including making 10 and decomposing a number leading to a 10

1.3.E(E) Explain strategies used to solve addition and subtraction problems up to 20 using spoken words, objects, pictorial models, and number sentences

1.OA.6 Add and subtract within 20, demonstrating fluency for addition and subtraction within 10. Use strategies such as counting on; making ten (e.g., 8 + 6 = 8 + 2 + 4 = 10 + 4 = 14); decomposing a number leading to a ten (e.g., 13 - 4 = 13 - 3 - 1 = 10 - 1 = 9); using the relationship between addition and subtraction (e.g., knowing that 8 + 4 = 12, one knows 12 - 8 = 4); and creating equivalent but easier or known sums (e.g., adding 6 + 7 by creating the known equivalent 6 + 6 + 1 = 12 + 1 = 13).

2.OA.22.OA.2 Fluently add and subtract within 20 using mental strategies. By end of Grade 2, know from memory all sums of two one-digit numbers.

This operations and algebraic thinking lesson covers how to memorize addition facts. The lesson includes research-based strategies and strategic questions that prepare students for assessments. In this lesson, students will practice the addition facts of numbers 2 through 10 by a combination of reading aloud and writing each fact many times in horizontal and vertical formats.

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### Subtract Numbers by Counting Down

This operations and algebraic thinking lesson covers subtracting numbers by counting down. The lesson includes research-based strategies and strategic questions that prepare students for assessments. In this lesson, students read the subtraction problem and then subtract the numbers by counting down. A number chart is provided to keep them on track. Word problems are also used. They finish by reading the fact family aloud.

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### Determine if Equations are True or False

(E) Understand that the equal sign represents a relationship where expressions on each side of the equal sign represent the same value(s)

2.4.A(A) Recall basic facts to add and subtract within 20 with automaticity

(Y1) Represent and solve simple addition and subtraction problems using a range of strategies including counting on, partitioning and rearranging parts (ACMNA015)

ACMNA030(Y2) Solve simple addition and subtraction problems using a range of efficient mental and written strategies (ACMNA030)

1.OA.7 Understand the meaning of the equal sign, and determine if equations involving addition and subtraction are true or false. For example, which of the following equations are true and which are false? 6 = 6, 7 = 8 - 1, 5 + 2 = 2 + 5, 4 + 1 = 5 + 2.

2.OA.2From CCSS "For example, which of the following equations are true and which are false? 6 = 6, 7 = 8 â€“ 1, 5 + 2 = 2 + 5, 4 + 1 = 5 + 2."

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### Add Three Numbers

Retrofit the existing lesson of adding three numbers to include word problem applications.

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### Count and Write Numbers to 120

This number and operations in base ten lesson covers how to count and write numbers to 120. The lesson includes research-based strategies and strategic questions that prepare students for assessments. In this lesson, students will read the numbers in a number chart and write in missing numbers.

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### Count and Write Numbers to 50

This number and operations in base ten lesson covers how to count and write numbers to 50. The lesson includes research-based strategies and strategic questions that prepare students for assessments. In this lesson, students will read the numbers in a number chart and write in missing numbers.

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### Count Objects 100-120

This number and operations in base ten lesson covers how to count objects from 100 to 120. The lesson includes research-based strategies and strategic questions that prepare students for assessments. In this lesson, students will read sentences that describe a specific number of objects in a group. Then, they will count on from that total to add a certain number more.

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### Count Objects 20-100

This number and operations in base ten lesson covers how to count objects from 20 to 100. The lesson includes research-based strategies and strategic questions that prepare students for assessments. In this lesson, students will read sentences that describe a specific number of objects in a group. Then, they will count on from that total to add a certain number more.