Estimating Measurements of Mass and Volume Using Metric Units
Students will be able to measure and estimate liquid volumes and masses of objects using standard units of grams (g), kilograms (kg), liters (l), and milliliters (ml).
- Pose the following questions to the class and discuss: Why do we measure things? Why do we need standardized units of measurement?
- Give students three minutes in small groups to brainstorm as many units and objects to measure that they can think of (2 liters of soda, yards on a football field, feet and inches to measure height, pounds to measure weight, etc.).
- Explain that there are two different systems of measuring, the United States Customary Units that is used by Burma, Liberia, and the US, and the International System of Units (or the metric system) which is used by the rest of the world.
- Tell students that in this lesson they will be learning about units in the metric system used to measure liquids (called Volume) and metric units for weight measurement, which is called Mass.
Explicit Instruction/Teacher modeling(15 minutes)
- First teach weight, focusing on grams and kilograms.
- Reference the worksheet Measurement: Grams and Kilograms to create a chart that shows the the two mass units: grams and kilograms. Include the abbreviation and one or two examples of each. These will serve as benchmarks as students learn and complete the exercises later.
- Demonstrate how much each unit is using the visuals you prepared (a paper clip and a bag of rice).
- Have students generate lists of everyday items that could be measured using grams and kilograms. Instruct them to estimate the measurement of their items using the benchmarks on your chart.
Guided practise(15 minutes)
- Distribute Measurement: Grams and Kilograms. Have students cut out the unit strips at the top (labeled Grams and Kilograms).
- Hold up some examples of everyday items in your classroom and ask students to show you what unit they would use to measure the item, kilograms or grams, by holding up the strip with the corresponding unit. Survey the class for understanding and discuss as necessary.
- Have students cut out cards with the items listed.
- Instruct students to work in pairs or groups to sort the examples. Using the Kilogram and Gram unit strips, have them place each item below the strip with the appropriate unit, using the guide on the worksheet as references.
- Review the solutions as a class and discuss.
Independent working time(15 minutes)
- Distribute Class set of Measurement: Liters and Milliliters.
- Instruct students to follow the same process, but this time on their own, cutting and matching examples with the appropriate measurement units.
- Provide additional benchmarks on the class chart or on the student chart (provided on the worksheet) that will assist in solving the exercises.
- Ask students to take pictures of items in their homes/communities that they could measure using grams, kilograms, liters, or milliliters, and bring the pictures to class. Allow them to email them to the teacher.
- Have students explore other metric units for mass and volume, such as milligrams. How much is a milligram? What kinds of things are measured with milligrams?
- Write three examples of common liquid or mass amounts on the whiteboard. Examples include: a glass of water, a boot, a backpack, or a pitcher of lemonade. Have students write on a ½ sheet of paper what unit they would use to measure each item.
- Turn the sheets in or review the guesses for reasonableness as a class and discuss.
Review and closing(5 minutes)
- Discuss the question: How does what I measure influence how we measure? This can be facilitated in pairs, small groups or whole class with large group share out.