Standard

Estimate lengths using units of inches, feet, centimeters, and meters.

Student language:

• "I can estimate the lengths of objects."

Explanation

About the Math, Learning Targets, and Rigor

This standard calls for students to estimate the lengths of objects using inches, feet, centimeters, and meters.

Estimation helps develop familiarity with the specific unit of measure being used. To measure the length of a shoe, knowledge of an inch or a centimeter is important so that one can approximate the length in inches or centimeters. Students should begin practicing estimation with items which are familiar to them (length of desk, pencil, favorite book, etc.).

Setting up personal benchmarks, such as the width of their pinky finger is a cm can be beneficial. See these useful benchmarks for measurement (for adults - so they will need to be adjusted for 2nd graders):

• First joint to the tip of a thumb is about an inch
• Length from your elbow to your wrist is about a foot
• If your arm is held out perpendicular to your body, the length from your nose to the tip of your fingers is about a yard

Resources

Videos

• Khan Academy
  • scroll to find 2.MD.3, click on a skill, watch videos on left side in each skill
• Learn Zillion

EngageNY Lessons

Extra Practice

• North Carolina Tasks
• Illustrative Math Tasks
• Howard County Tasks
  • Click on 2nd grade at bottom, then 2.MD.3
• Common Core Sheets

Released Assessment Questions

2.MD.3 Student Example

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