In this lesson, students count by sixes, composing up to and then over the next ten. For example, they might count 6, 12, 18, and then add 18 + 2 + 4 to make 24. (In doing so, they utilize the "make a ten" strategy first introduced in Grades 1. and 2.) Students use number bonds to decompose and identify appropriate number pairs, and then move to using mental math as patterns in the sequence of ones digits emerge. They also review the relationship between multiplication and division as a strategy for multiplication and division.