In previous lessons, students measured lengths in centimeters with physical units and the rulers they constructed.
The purpose of this lesson is to build on their experiences with centimeters to estimate lengths in centimeters and measure lengths with a centimeter ruler. In Activity 1, students estimate the length of objects in the classroom. Objects have been suggested, but they can be changed based on what is available in the classroom. Most of the objects students use to estimate and measure length for the purposes of this lesson should be 5–30 cm long. At least one object should be between 50–90 cm long to give students the opportunity to estimate longer objects and an opportunity to experience the need to iterate a ruler to find a longer measurement in anticipation of future lessons. In Activity 2, students measure the actual length of the objects.
- Action and Expression
- Estimate lengths in centimeters.
- Use standard rulers to measure length in centimeters.
- Let’s estimate and measure in centimeters.
- Each group of 2 needs access to several objects between 5–30 cm long and at least one object between 50–90 cm long.
|Activity 1||15 min|
|Activity 2||20 min|
|Lesson Synthesis||10 min|
Teacher Reflection Questions
- Estimate and Measure (1–4), Stage 1: Choose Your Unit (Addressing)
- Five in a Row: Addition and Subtraction (1–2), Stage 6: Add within 100 with Composing (Supporting)
Print Formatted Materials
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