Lesson objective: Use conversions to compare metric measurements.

This lesson provides an opportunity for students to apply their knowledge and understanding of the metric system to a mathematical situation. Students are given a set of measurements of metric length, mass, and capacity. There are three bears: a small baby bear, a middle sized bear, and a large bear. Students need to determine which measurements of mass, capacity, and height belong to each bear.

Key Concept students will use:

- The metric system is similar to the base 10 place value system where the value of the digit in one place is 10 times greater than the digit to the right.

Skills students will use:

- knowledge of metric measurements: length is measured in meters, mass is measured in grams, and capacity is measured in liters (Grade 3, Unit 14)
- multiplication of one-digit whole numbers by multiples of 10 using strategies based on place value and properties of operations (3.NBT.A.3)
- metric conversions

Students engage in Mathematical Practice 7 (look for and make use of structure) as they use their knowledge of the base 10 place value system and compare it to the metric system. Students use the relationship between different units of measure within a system to convert larger units into smaller units that represent the same quanitity.

**Key vocabulary: **

- capacity
- centimeter
- gram
- height
- kilogram
- mass
- meter
- milliliter
- liter
- weight