OA-Add+and+subtract+within+20

1.OA.5. Relate counting to addition and subtraction (e.g., by counting on 2 to add 2). 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). || ===‍**Anchor Standard/Mathematical Practice(s)**=== 1.SE.1.1 Use technology hardware and software responsibly. || ===‍ Revised Bloom's Level of thinking === remembering-number facts understanding- additon and subtraction applying- properties of operations ||
 * ===**Common Core Standards**===
 * MP.2. reason abstractly and quantitatively.**
 * MP.7. Look for and make use of structure**
 * MP.8. Look for and express regularity in repeated reasoning.** ||
 * ===‍**Information Technology Standard**===

‍**I can...**
count on to add.

count back to subtract.

add fluently using different strategies.

subtract fluently using different strategies.

‍**Sample Assessments**
===‍**Differentiation: have addition and subtraction races to build fluency with facts. Show relationship between addition and subtraction with missing addends. Subtraction bowling-students start with 9 pins, bowl and write a subtraction sentence for what was knocked down. Use pop cubes to model addition and subtraction.**===

‍**Intervention: small group-lessons on connecting counting and number sequence to operations**

 * number line game**

‍**Enrichment: independent problem solving and listing strategy or solve problems using all strategies**

 * game**

‍**Instructional Resources: five frame, tens frame,**
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‍**Notes and Additional Information**
When solving addition and subtraction problems to 20, First Graders often use counting strategies, such as counting all, counting on, and counting back, before fully developing the essential strategy of using 10 as a benchmark number. Once students have developed counting strategies to solve addition and subtraction problems, it is very important to move students toward strategies that focus on composing and decomposing number using ten as a benchmark number, as discussed in 1.OA.6, particularly since counting becomes a hindrance when working with larger numbers. By the end of First Grade, students are expected to use the strategy of 10 to solve problems. In First Grade, students learn about and use various strategies to solve addition and subtraction problems. When students repeatedly use strategies that make sense to them, they internalize facts and develop fluency for addition and subtraction within 10. When students are able to demonstrate fluency within 10, they are accurate, efficient, and flexible. First Graders then apply similar strategies for solving problems within 20, building the foundation for fluency to 20 in Second Grade.