Key Concept: Strategies can help to add and subtract quantities efficiently.

Topic Overview | Standards Alignment | #### Common Core

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

1.OA.C.5 Relate counting to addition and subtraction (e.g.by counting on 2 to add 2).

1.OA.C.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).#### Georgia

MGSE1.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.

MGSE1.OA.5 Relate counting to addition and subtraction (e.g., by counting on 2 to add 2).

MGSE1.OA.6 Add and subtract within 20. a. 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). b. Fluently add and subtract within 10. IEP Goals

In this topic, students develop their ability to solve equations using double fact strategies and make-a-ten strategies.

1.OA.C.5 Relate counting to addition and subtraction (e.g.by counting on 2 to add 2).

1.OA.C.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).

MGSE1.OA.5 Relate counting to addition and subtraction (e.g., by counting on 2 to add 2).

MGSE1.OA.6 Add and subtract within 20. a. 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). b. Fluently add and subtract within 10.

1. Given an addition or subtraction fact within 20, the student will solve using a strategy for 5 out of 6 examples by the completion of the IEP.

O.4-1-4 Double Fact Strategies to 18 |

View Guided Lesson Students use double facts within 18 to efficiently determine the sums of double plus one facts. (12-20 min)

O.4-1-6 Decompose to Subtract Within 20 |

View Teacher-Facilitated Lesson Students apply their understanding of decomposition to make a ten when subtracting within 20. (35-45 min)

In this unit, students develop strategies to solve addition and subtraction equations. Strategies include counting on or back, making ten, and using a known fact to solve an unknown one.

1.OA.C.5 Relate counting to addition and subtraction (e.g.by counting on 2 to add 2).

1.OA.C.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).

MGSE1.OA.5 Relate counting to addition and subtraction (e.g., by counting on 2 to add 2).

MGSE1.OA.6 Add and subtract within 20. a. 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). b. Fluently add and subtract within 10.