Unit 3, Lesson 2
Measuring with Different-Size Units (Optional)
Grade 6
Preparation
Lesson Narrative
This optional lesson further develops students’ understanding of standard units of length, volume, weight, and mass through the tactile experiences of measuring objects. The main idea is that it takes more of a smaller unit and fewer of a larger unit to measure the same quantity.
Students begin by comparing two non-standard units of length. They determine whether it would take more regular paper clips or more jumbo paper clips to measure the length of a piece of paper. Then, students engage in similar exercises involving various standard units. In groups, they rotate through up to five measurement stations, using two units to measure one or more quantities at each station. By reasoning repeatedly, students notice regularity (MP8)—that a measurement in a smaller unit results in a greater value than the same measurement in a larger unit.
- Generalize (orally and in writing) that it takes more of a smaller unit or fewer of a larger unit to measure the same quantity.
- Given a measurement in one unit, estimate what would be the same amount expressed in a different unit, and explain (orally) the reasoning.
Let’s measure things.
Required Materials
Activity 1
Required Preparation
Prepare to display or distribute paper clips in two sizes: regular and jumbo.
Identify where in the classroom each measuring station will be set up. Preparation varies based on whether students will use physical or digital materials.
If using physical materials, prepare each station as follows:
- Station 1:
- From the first page of the blackline master, print onto card stock the net for the box that is 2 in by 2 in by 4 in, cut it out, and assemble it.
- Provide at least twenty (20) inch cubes, one (1) centimeter cube, and thirty (30) 10 cm rods. The centimeter cube and 10 cm rods can come from a set of base-ten blocks or Cuisenaire rods. However, base-ten blocks are preferable so students can see that one rod is composed of 10 cm cubes. Wooden inch cubes are available inexpensively at craft stores.
- Station 2:
- Identify something in the classroom that is about 20 feet long. Prepare a way to communicate the length to be measured without giving away the measurement.
- Provide foot-long rulers and at least 2 meter sticks.
- Station 3:
- Provide 1 gallon-sized jug, 5 quart-sized bottles, 5 liter-sized bottles, and a funnel (if available).
- Fill the gallon jug with water.
- Station 4:
- Prepare a scale that can measure mass and weight in grams, kilograms, ounces, and pounds. (If such a scale is not available, consider using two scales that—when used together—can give the mass and weight measurement of an object in these four units.)
- Prepare 6–8 common household items for students to weigh.
- Station 5:
- Prepare a 100 ml graduated cylinder, a teaspoon, a straightedge for leveling off the teaspoon, and a small bowl with at least cup of salt. Place everything on a tray for catching spills.
If using digital materials, acquire a device that can play a video or run an applet for each station. Open the following links:
- Station 1: "Cubic Inches and Cubic Centimeters" video, available at https://im612.org/Measurement_Station_1
- Station 2: "Meters and Feet" video, available at https://im612.org/Measurement_Station_2
- Station 3: "Quarts and Liters" video, available at https://im612.org/Measurement_Station_3
- Station 4: Two options:
- "Grams, Kilograms, Ounces, and Pounds" video available at https://im612.org/Measurement_Station_4
- "Digital Scale" applet, available at http://ggbm.at/eQQVYB7D
- Station 5: "Milliliters and Teaspoons" video, available at https://im612.org/Measurement_Station_5
Even if students are watching the video or using the digital applet at Station 4, consider preparing some real objects (each labeled with its weight or mass) for students to hold.