Students will be able to use metric units of length.
- Watch Measuring to the nearest cm and mm by 2minutemath
- After watching the video, ask your students what they can measure in real life.
- Provide students with visuals of key takeaways from the video.
- Provide students with a table showing examples of centimeter to millimeter conversion, as shown in the video.
- Have students explain key points from the video in their home language with a small group of peers who speak the same language, if possible.
- Ask students to explain, using their own words, what the teacher in the video was showing.
- Provide students with an example from the video in centimeters and see if they are able to convert centimeters to millimeters, using what they learned from the video.
Explicit Instruction/Teacher modeling(15 minutes)
- Give your students rulers, and ask them to see what units of length they see.
- Review how to measure an object with a ruler by starting at the zero mark and measuring straight across.
- Acknowledge that some objects aren't exact, so decimals or fractions are necessary to record an exact measurement.
- Demonstrate on the whiteboard how to measure 3.4 centimeters. Draw several lines for practice.
- Provide students with a few real objects to use as they practice measuring.
- Provide an example of decimals and fractions in visual form for students to paste in their math journals.
- Encourage students to share what they notice about the ruler, using a sentence stem for support, such as:
- I notice the ruler is ____.
- Ask students to turn and talk to a partner, sharing out what they notice about the ruler.
- Have students jot down key vocabulary in their math journals, such as fraction and decimal.
Guided Practice(15 minutes)
- Demonstrate to students that 3.4 centimeters can also be written as 34 millimeters.
- Instruct your students to measure lines of different sizes and write them the two ways that they just learned.
- Allow students to work in a teacher-led, small group.
- Encourage students to use a sentence frame to share out their answers:
- The line is ____ centimeters and ____ millimeters.
- Have students explain the steps to measure the line in centimeters and convert the centimeters to millimeters using sequencing words (first, next, then, finally).
Independent working time(15 minutes)
- Give your students the Length in Centimeters worksheet to complete.
- Have students stay in the teacher-led, small group to complete the worksheet.
- Ask students to share out their understanding of using a ruler and centimeters to find the length of the shoes in their home language (L1), if possible.
- Allow students to work in partnerships.
- Encourage students to check their answers with a partner, using the following sentence frame to support student discussion:
- The answer I got was ____ centimeters because ____. Do you agree or disagree?
Enrichment: Have your students complete the Measuring Length in Centimeters worksheet.
Support: Before working on decimals, have your students master the concept of measuring to a whole number. Throughout this activity, have them round up or down to the nearest whole number instead of using decimals or fractions.
- Circulate and provide support where needed.
- Make sure that your students are using their rulers from the correct side.
- Collect student work as a formative assessment to check for understanding.
- Provide students with a real-life object to measure from the classroom. Have them measure the object using centimeters and convert the centimeters to millimeters. Jot down notes about student ability to complete the task.
- Provide students with a sentence frame to share their answer, such as:
- ____ is ____ centimeters long and ____ millimeters long.
- Ask students to explain orally how they figured out the measurements of the shoes.
Review and closing(5 minutes)
- Ask students to complete a think-pair-share, responding to one of the following sentence stems:
- One of the units of length we learned about today was ____.
- My favorite part of the lesson was ____.
- I feel ____ (good/okay/confused) about using a ruler because ____.
- Allow students to share their answers in their home language (L1).
- Provide sentence frames to support students in sharing out their answers.