Lesson objective: Understand that multiplication works the same when working with measurement values like liters, grams, or kilograms.

Students bring prior knowledge of multiplication from from 3.OA.A.3 and grams, kilograms, and liters from 3.MD.A.2. This prior knowledge is extended to measurement values as students put together equal groups of liters, grams, and kilograms using multiplication. A conceptual challenge students may encounter is thinking about numbers as representing groups of liters, grams or kilograms.

The concept is developed through work with number lines and tape diagrams which helps support the development of multiplication as putting together equal groups.

This work helps students deepen their understanding of operations because students realize they can use multiplication to solve problems involving measurement quantities (including liquid volumes and masses of objects).

Students engage in Mathematical Practice 5 (Model with mathematics) as they use a variety of tools and strategies to solve problems putting together equal groups of measurement values. Students may use number lines, tape diagrams, equations, pictures or other strategies.

**Key vocabulary:**

- decompose
- equal groups
- multiplication
- number line
- tape diagram