Multiplication and Division (2) - Multiply 3 digits by 2-digits (arithmetic) - Presentation

In a comprehensive lesson on multiplication and division, students are challenged to expand their understanding of long multiplication by learning to multiply three-digit numbers by two-digit numbers. The lesson begins with a discussion prompt, encouraging students to consider the differences and similarities when multiplying larger numbers. For example, they are presented with the problem 354 x 32 and prompted to think about the process involved. The lesson includes a series of activities, starting with one that asks students to complete multiplications such as 132 x 14, highlighting the importance of the zero in multiplication and how it affects the placement of numbers in the calculation.

The subsequent activities involve more complex problems, such as multiplying 642 by 34, and even applying these skills to real-world scenarios, like calculating the area of a park measuring 134 yards by 68 yards. Students are also encouraged to engage in reasoning exercises, such as observing patterns in a sequence of multiplications (e.g., 32 x 111, 33 x 111, and so on) and determining when these patterns break due to the need for exchanges in the calculations. The lesson also includes error correction exercises, where students must identify and fix mistakes in given calculations, such as when zeros are omitted or exchanges are not properly carried out. Independent work tasks further reinforce the concept, with long multiplication problems and exercises that require filling in missing numbers in calculations. Discussion questions round off the lesson, prompting students to delve deeper into numerical concepts such as the significance of one more or one less in a given number.