In Topic B, students learn that intervals do not have to be whole numbers but can have fractional values that
facilitate recording measurement data with greater precision. In Lesson 5, they generate a six-inch ruler
marked in whole-inch, half-inch, and quarter-inch increments, using the Module 5 concept of partitioning a
whole into parts. This creates a conceptual link between measurement and recent learning about fractions.
Students then use the rulers to measure the lengths of precut straws and record their findings to generate
measurement data (3.MD.4).
Lesson 6 reintroduces line plots as a tool for displaying measurement data. Although familiar from Grade 2,
line plots in Grade 3 have the added complexity of including fractions on the number line (2.MD.9, 3.MD.4).
In this lesson, students interpret scales involving whole, half, and quarter units in order to analyze data. This
experience lays the foundation for them to create their own line plots in Lessons 7 and 8. To draw line plots,
students learn to choose appropriate intervals within which to display a particular set of data. For example,
to show measurements of classmates’ heights, students might notice that their data fall within the range of
45 to 55 inches and then construct a line plot with the corresponding interval.
Students end the module by applying learning from Lessons 1–8 to problem solving. They work with a
mixture of scaled picture graphs, bar graphs, and line plots to problem solve using both categorical and
measurement data (3.MD.3, 3.MD.4).