Common Core Math Grade 5 Multiplication as Scaling

In previous grades, students understood multiplication as equal groups.
This lesson introduces multiplication as scaling. Students already know that multiplying a number by 1 results in the original number. Now they learn that multiplying a number by a whole number greater than 1 results in a product greater than the original number, and multiplying a number by a fraction less than 1 results in a product less than the original number. Students connect these concepts to gain a better understanding of multiplication as scaling. They recognize 4 x 5as 4 times as big as 5 and 1/2 x 5 as 1/2 as big as 5 without performing computation.
Students use the concept of multiplication as scaling in mathematical contexts such as dilations and in real-world contexts such as using scale models. Understanding multiplication as scaling prepares students for Grade 6 work with ratios and proportional reasoning.
Aligned with Common Core 5.NF.B.5a/b