Unit Conversions

1. Establish benchmarks for the metric units of a kilogram and gram. 
2. Use the meaning of the prefix “kilo-” to deduce that a kilogram is 1,000 times as heavy as a gram. 
3. Establish benchmarks for the metric units of a liter and milliliter. 
4. Use the meaning of the prefix “milli-” to deduce that a liter is 1,000 times as capacious as a milliliter. 
5. Use these relationships to convert measurements from a larger metric mass or capacity units to a smaller unit (MP.7, MP.8). 
6. Use these relationships to convert measurements from mixed metric mass or capacity units to a smaller unit (MP.7, MP.8).
7. Solve one-step word problems that require metric capacity or mass unit conversions (MP.4).

As the Geometric Measurement Progression states, “the Standards do not differentiate between weight and mass. Technically, mass is the amount of matter in an object. Weight is the force exerted on the body by gravity. On the earth’s surface, the distinction is not important (on the moon, an object would have the same mass, would weigh less due to the lower gravity)” (Progressions for the Common Core State Standards in Mathematics, K-5 Geometric Measurement, p. 2). Thus, the term “mass” is used through Lesson 2 in reference to metric mass measurement but the term “weight” is used throughout Lesson 6 in reference to customary weight measurement. Enforcing the correct usage with students isn’t necessary, but it could be discussed if a student raises the issue.

• Problem Set

• Problem Set Answer Key