2nd Grade Unit 7: Making Connections Between Multiplication and Division

Unit Driving Question

How are multiplication and division related?

This unit is intended to stretch above second grade standards into third grade. Some of the tasks in this unit will use third grade standards to develop the connection between multiplication and division.  Each task will allow students to use manipulatives and models to problem solve.

Key Resources 

1. Dots in ArraysStudents will begin by making observations of an array and describe it using addition terms as described in the task. Then extend the lesson by having the students describe the array with multiplication.  Next, challenge the students to make a division problem using the array, then model how they would solve it. 
2. Partitioning Rectangles into Squares  Using an area model, students will divide a rectangle into squares. Then the students will determine the ways to express this with a number sentence using both multiplication and division.  To extend this task, have students create different area models and write more number sentences.
3. Snappy Math - Multiplication with Arrays Learn to read an array and link the array with a multiplication and division equation.
4. Giddy Up, Round UpIn this lesson, students explore the relationship between multiplication and division through play and discussion.
5. Cookie BakingUsing real-world problem solving, students will use models to solve and explain the relationship between multiplication and division.  As the task continues, the problems require more rigor and reasoning to develop an answer.
6. Isabella's GardenStudents will problem solve by using models, manipulatives, multiplication, and division to reason their way through the task to explain multiple strategies to solve the problem. 

Unit Re-Engagement

Planting Carrots - Using the digits 1 through 9, at most one time each, to fill in the blanks to make the following problem true.

• Sarah planted __ __ carrots in her garden. She planted them in __ rows. Each row had __ carrots.
• Is there more than one strategy that could solve this problem?  
• Can you find two more solutions to this problem?
• How are the different strategies alike?