NBT 5: Multiply a whole number of up to four digits by a one-digit whole number, and multiply two two-digit numbers, using strategies based on place value and the properties of operations. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models.
Learning Targets
· I can multiply a multi-digit number by a one-digit number.
· I can demonstrate multiplication of two two-digit numbers using rectangular arrays, place value, and the area model.
About the Math
In their NCSM article, Fuson and Beckman, describe how standard algorithms are developed in mathematics. There are diverse ways to multiply multi-digit numbers. Some of these are listed below. Students should not be expected to master or utilize each or all of these for a given situation. The intent is that students can use properties and place value strategies (including partial products, which can be considered an algorithmic approach as well). Other algorithms include: Understanding Multiplication (Long Multiplication Algorithm, Traditional American Algorithm), Understanding Multiplication (Egyptian Multiplication), Understanding Multiplication (Lattice Method), and Understanding Multiplication (Russian Peasant). Important vocabulary to lift up includefactor, product, array, area model.
Learning Targets
· I can multiply a multi-digit number by a one-digit number.
· I can demonstrate multiplication of two two-digit numbers using rectangular arrays, place value, and the area model.
About the Math
In their NCSM article, Fuson and Beckman, describe how standard algorithms are developed in mathematics. There are diverse ways to multiply multi-digit numbers. Some of these are listed below. Students should not be expected to master or utilize each or all of these for a given situation. The intent is that students can use properties and place value strategies (including partial products, which can be considered an algorithmic approach as well). Other algorithms include: Understanding Multiplication (Long Multiplication Algorithm, Traditional American Algorithm), Understanding Multiplication (Egyptian Multiplication), Understanding Multiplication (Lattice Method), and Understanding Multiplication (Russian Peasant). Important vocabulary to lift up includefactor, product, array, area model.