Warm Up – Complete in math section of your 5-subject notebook Ms. Byrne asked her students to solve 53 x 28 using expanded notation. Show what the students should have done to complete this problem.

Alignment Lesson: Connect Multiplication Strategies

Short Cut A.k.a Old School

Rectangle Sections 67 x x x 3 40 x 7 7 x 3

Rectangle Rows 43 x x 40 = 2, x 3 = 201 Add ‘Em Up 2, ,881

Expanded Notation 43 x = AND 67 = x 60 = 2,40040 x 7 = x 60 = 1803 x 7 = 21 Add ‘Em Up …2, = 2,881

Find “Connect Multiplication Strategies” in your Notebook Add another section for three digit factor Example: 427 x x 3020 x x 820 x 8 30 x 7 7 x 8 Add ‘Em Up!!

Standard Algorithm 427 x 38

How does the Rectangle Sections model connect to the standard algorithm? The sum of the bottom row of partial products is the same as the first row in the standard algorithm. This is because the bottom row in the Rectangle Sections model is showing 8 x 427 just as the first row in the standard algorithm does. The sum of the top row in the Rectangle Sections model is the same as bottom row in the standard algorithm. This is because the top row in the Rectangle Sections model is showing 30 x 427 just as the bottom row of the standard algorithm does.

Continue with examples in Alignment Lesson *Student pages: Day 5- Connect Multiplication Strategies