This video lesson reviews how to rewrite expressions using the properties of operations: the commutative property of addition, the commutative property of multiplication, the associative property of addition, the associative property of multiplication, the identity property of addition, and the identity property of multiplication. This video provides sample problems for your class to solve as you review each property.

This video lesson demonstrates how to use arrays to find products. How many shampoo bottles can the display hold? To solve this problem, students build an array with place value blocks, break apart the array into tens and ones, and write a number sentence to represent this. Then, they add the partial products to find the product of the array.