Lesson objective: Understand that the same object can be measured multiple times to generate data.

Students bring prior knowledge of measurement from 2.MD.A.1. This prior knowledge is extended to repeatedly measuring the same object as students measure and record the height of a growing bean seed. A conceptual challenge students may encounter is using inches and centimeters interchangeably.

The concept is developed through work with ruler and data table, which allow students to repeatedly measure an object and record the data they collect.

This work helps students deepen their understanding of whole numbers because they are using whole numbers on a ruler to represent the growth of a bean plant.

Students engage in Mathematical Practice 6 (Students will measure with precision using standard units in order to collect data sets), as they grow and repeatedly measure the growth of the bean seed and record the collected data on their data table.

**Key vocabulary:**

- centimeter
- height
- inch
- measurement

**Special materials needed:**

- bean seeds
- cups (to plant seeds in)
- ruler
- soil