Lesson objective: Understand the relationship between multiplication and division to multiply and divide within 100.

Students bring prior knowledge of the relationship between multiplication and division from 3.OA.C.7. This prior knowledge is extended to understanding multiplication and division as inverse operations as students use multiplication to solve a division problem. A conceptual challenge students may encounter is setting up the division problem as a multiplication problem.

The concept is developed through work with equal groupings, which helps link multiplication and division.

This work helps students deepen their understanding of operations because they use the relationship between the operations of multiplication and division to become fluent at solving single-digit multiplication and division problems.

Students engage in Mathematical Practice 8 (Look for and express regularity in repeated reasoning) as they notice repetitive actions in computation when solving problems. For example, students can use skip counting or repeated addition or subtraction to solve a multiplication or division problem.

**Key vocabulary:**

- division
- inverse opeations
- multiplication
- relationship