In Unit 7, students solve problems involving measurement and estimation of intervals of time, liquid volumes, and masses of objects. The unit, while major work itself, also “support[s] the Grade 3 emphasis on multiplication and the mathematical practices of making sense of problems (MP.1) and representing them with equations, drawings, or diagrams (MP.4)” (GM Progression, p. 18).
Students begin by building on their understanding of telling time to the nearest five minutes from Grade 2 (2.MD.7) to tell and write time to the nearest minute using analog and digital clocks (3.MD.1). Students see that an analog clock is a portion of the number line shaped into a circle. Just as students used a number line to represent sums and differences in Grade 2 (2.MD.6), students use the number line to represent addition and subtraction problems involving elapsed time in minutes and durations of time (3.MD.1).
Building on the estimation skills with length gained in Grade 2 (2.MD.3), students in Grade 3 use the metric units of kilograms, grams, liters, and milliliters to estimate the masses and liquid volumes of familiar objects (3.MD.2). Students also measure objects in those units, reading the measurement scales on analog tools such as beakers. Finally, just as students solved word problems involving lengths in Grade 2 (2.MD.5), students solve word problems involving masses or volumes given in the same metric units (3.MD.2).
Students will rely on the work of this unit to convert from a larger unit to a smaller unit in Grade 4 (4.MD.1) and from a smaller unit to a larger one in Grade 5 (5.MD.1), as well as to solve multi-step word problems involving intervals of time, liquid volumes, and masses of objects, including problems involving simple fractions or decimals (4.MD.2, 5.MD.1). Beyond the direct connections to Grade 5 Common Core State Standards, “measurement is central to mathematics, to other areas of mathematics (e.g., laying a sensory and conceptual foundation for arithmetic with fractions), to other subject matter domains, especially science, and to activities in everyday life. For these reasons, measurement is a core component of the mathematics curriculum” (GM Progression, p. 1).
Pacing: 15 instructional days (12 lessons, 2 flex days, 1 assessment day)
For guidance on adjusting the pacing for the 2021-2022 school year, see our 3rd Grade Scope and Sequence Recommended Adjustments.