In this activity, students rotate in groups through five different stations, where they measure one or more quantities using different units. Afterward, students answer questions that prompt them to make sense of the numerical values of the measurements and the sizes of the units. 

Here are the quantities being measured and the units used at each station:

• Station 1: Volume of a box, in cubic inches and cubic centimeters
• Station 2: Length, in meters and feet
• Station 3: Volume of water, in gallons, quarts, and liters
• Station 4: Weights and masses of 2–3 objects, in ounces, pounds, grams, and kilograms
• Station 5: Volume of salt, in milliliters and teaspoons

In the digital version of the activity, students watch videos that show measurements being taken. In Station 4, they also have the option to use an applet to explore units of mass and weight. The applet allows students to simulate the use of a digital scale to measure the mass or weight of various objects. Consider using the digital version if the materials needed to physically perform measurements are not readily available or if preparation time is limited. Using digital materials for some stations and physical materials for others is also an option. See Required Preparation for more details.

A note about weight and mass:

Students who are able to distinguish between weight and mass might say that they cannot accurately compare the measurements or put the units in order by size. Clarify that we are talking only about the weight of the objects on Earth’s surface.

Though much of the discussion will take place within groups, spend a few minutes ensuring that everyone understands the answers to the five questions. To conclude the activity, invite students to share anything that surprised them from the measuring work.