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K.OA.A.3 Understand addition as putting together and adding to, and understand subtraction as taking apart and taking from. 3. Decompose numbers less than or equal to 10 into pairs in more than one way, e.g., by using objects or drawings, and record each decomposition by a drawing or equation (e.g., 5 = 2 + 3 and 5 = 4 + 1). Unpacked Decomposing (splitting) a number is a foundational skill in number sense. The mastery of this skill helps students understand that a quantity can be composed of two smaller quantities in different ways. Further, these sets can be arranged in a variety of ways and the sum total is always the same; for example, we can reorder addends and the sum will be the same (4 + 2 = 2 + 4). Students will begin to develop the ability to record the results of compositions and decompositions of sets using numbers, objects and pictures. This skill lays a firm foundation for understanding of operations and algebraic thinking. Students develop an understanding of part-whole relationships as they recognize that a set of objects (5) can be broken into smaller sub-sets (3 and 2) and still remain the total amount (5). In addition, this objective asks students to realize that a set of objects (5) can be broken in multiple ways (3 and 2; 4 and 1). Thus, when breaking apart a set (decompose), students use the understanding that a smaller set of objects exists within that larger set (inclusion). Example: “Bobby Bear is missing 5 buttons on his jacket. How many ways can you use blue and red buttons to finish his jacket? Draw a picture of all your ideas. Students could draw pictures of: 4 blue and 1 red button, 3 blue and 2 red buttons, 2 blue and 3 red buttons, 1 blue and 4 red buttons In Kindergarten, students need ample experiences breaking apart numbers and using the vocabulary “and” & “same amount as” before symbols (+, =) and equations (5= 3 + 2) are introduced. If equations are used, a mathematical representation (picture, objects) needs to be present as well. Students may use drawings to show different number pairs for a given number. For example, students may draw 5 objects, showing how to decompose in several ways. Examples of what this work might look like for students: Speaking Level 2 Emerging Demonstrate an understandin g of decomposing numbers less than or equal to 10 into pairs in more than one way, Level 3 Developing Demonstrate an understandin g of decomposing numbers less than or equal to 10 into pairs in more than one way, Level 4 Expanding Demonstrate an understandin g of decomposing numbers less than or equal to 10 into pairs in more than one way, Level 5 Bridging Demonstrate an understanding of decomposing numbers less than or equal to 10 into pairs in more than one way, e.g., by using objects or drawings, and recording each decompositio n using a 5 frame and explaining to the teacher. e.g., by using objects or drawings, and recording each decompositio n using a 5 frame and explaining to a partner. e.g., by using objects or drawings, and recording each decompositio n on a chart while explaining to a partner. e.g., by using objects or drawings, and recording each decompositio n on a chart and explaining to a cooperative group. e.g., by using objects or drawings, and recording each decomposition and teaching the concept to a small group. ELD Standard #3: English Language Learners communicate information, ideas, and concepts necessary for academic success in the content area of Mathematics. Level 6 Reaching Level 1 Entering Demonstrate an understandin g of decomposing numbers less than or equal to 10 into pairs in more than one way,