Topic A Multiplication and the Meaning of the （主题一个乘法的意义）.pdf

New York State Common Core 3 Mathematics Curriculum G R A D E GRADE 3 • MODULE 1 Topic A Multiplication and the Meaning of the Factors 3.OA.1, 3.OA.3 Focus Standard: 3.OA.1 Interpret products of whole numbers, e.g., interpret 5 × 7 as the total number of objects in 5 groups of 7 objects each. For example, describe a context in which a total number of objects can be expressed as 5 × 7. Instructional Days: 3 Coherence -Links from: G2– M6 Foundations of Multiplication and Division -Links to: G4– M3 Using Place Value Understanding and Properties of Operations to Perform Multi- Digit Multiplication and Division Lesson 1 introduces students to multiplication starting with the concept of repeated addition, familiar from Grade 2. Students use repeated addition to find totals, for example from scattered stars grouped equally within larger circles. They learn to recognize each circled group of stars as a unit, and count units using the language of groups and unit form. “3 groups of 5 stars make 15 stars,” or “3 fives make 15.” By the end of Lesson 1 students use the multiplication symbol to represent these descriptions as more efficient multiplication facts. In Lesson 2, students relate the equal groups of objects in scattered configurations from Lesson 1 to the array model, exploring the correspondence between 1 equal group and 1 row. They begin to distinguish between the number of groups and the size of groups as they count rows and how many in 1 row to write multiplication facts. Students recognize the efficiency of arrays as they skip-count to find totals. By the end