EngageNY 60 min(s)

In this lesson, students look for and practice a more efficient way to add by bundling. They calculate repeated addition sums by grouping the addends into pairs. For example, they add 5 + 5 + 5 + 5 using known double facts: (5 + 5) + (5 + 5) = 10 + 10 = 20.