Lesson objective: Understand that the length of an object can be measured using two different measurement systems.

Students bring prior knowledge of measurement from 1.MD.A.2. This prior knowledge is extended to measurement using standard units as students choose and use measurement tools appropriately. A conceptual challenge students may encounter is reasoning and analyzing the relationship between the unit size and number of units in a measured length.

This work helps students deepen their understanding of operations because students will count using whole numbers to determine the number of units in the measured length of an object while exploring two different systems of measurement.

Students engage in Mathematical Practice 6 (Attend to precision) as they explore two different systems of measurement and the related tools and units for both the metric and customary systems.

**Key vocabulary:**

- foot
- inch
- length
- meter
- meter stick
- ruler
- tape measure
- tool
- unit of measure
- yard
- yardstick

**Special materials needed: **

- centimeter cubes
- linking cubes
- centimeter ruler
- inch ruler
- meter stick