MA.2.M.1.2

Measure the lengths of two objects using the same unit and determine the difference between their measurements.

Clarifications

Clarification 1: Within this benchmark, the expectation is to measure objects to the nearest inch, foot, yard, centimeter or meter.
General Information
Subject Area: Mathematics (B.E.S.T.)
Grade: 2
Strand: Measurement
Status: State Board Approved

Benchmark Instructional Guide

Connecting Benchmarks/Horizontal Alignment

 

Terms from the K-12 Glossary

  • NA

 

Vertical Alignment

Previous Benchmarks

 

Next Benchmarks

 

Purpose and Instructional Strategies

The purpose of this benchmark is to directly compare the length of two objects measured using the same unit and determine the difference. 
  • Instruction includes selecting the appropriate tool to measure. 
  • Instruction includes helping a student choose a method they can use reliably to determine the difference. 
  • Instruction includes helping students record the appropriate measurement when the object falls between two whole number measurements.

 

Common Misconceptions or Errors

  • Students may always choose to use a ruler to measure length, even when the object is longer than a ruler.
  • Students may count all tick marks, not just the whole-unit marks, when reading a measurement tool and misread the nearest whole unit.
  • Students may add instead of subtract to find the difference between the two lengths or try to subtract the longer length from the shorter length because they measured them in that order.

 

Strategies to Support Tiered Instruction

  • Instruction includes helping students understand that when we measure longer objects, it is best to use a tape measure, yard stick or meter stick and use larger units, if possible.
    • For example, ask students to use their inch or centimeter rulers to measure the length of the whiteboard or another long object in the room. Then show them how to use a tape measure (or meter or yard stick) to measure. Note that it is easier to measure with these tools.
    • Next, have students note that they could find the number of inches or centimeters more accurately with the longer tool because they didn’t have to keep moving their tool.
    • Then, have students notice the different units of measure on the measurement tool (meters with the centimeters and feet and yards with the inches).
    • Model how to count by meters, feet and yards on the measurement tool and have students practice measuring objects in these units. Talk about the number of inches it takes to measure an object versus measuring the same object with feet.
  • Instruction includes modeling a think aloud using a ruler as a number line to show how a measurement is about ____ units when the object falls between two whole number measurements.
    • For example, show a ruler with just the whole number tick marks. Measure an object that is closer to 3 inches and measure an object that is closer to 4 inches.

ruler and eraser

The _eraser_ is about _3_ inches long. The _crayon_ is about _4_ inches long.

 

Instructional Tasks

Instructional Task 1 (MTR.4.1

Provide students with an object of a given measurement in various units. 
  • Part A. Find objects in the classroom or that are shorter or longer than the given object and find the difference using the common unit. 
  • Part B. Discuss which tool was more appropriate to use and what strategy was used to find the difference.

 

Instructional Items

Instructional Item 1 

A pair of scissors measure 22 centimeters long, and a glue stick measures 14 centimeters long. Which statement below is true about the measurement of the objects? 
  • a. The glue stick is 9 cm. longer than the scissors. 
  • b. The glue stick and scissors are 8 cm. long. 
  • c. The scissors are 8 cm. longer than the glue stick. 

 

*The strategies, tasks and items included in the B1G-M are examples and should not be considered comprehensive

Related Courses

This benchmark is part of these courses.
5012040: Grade Two Mathematics (Specifically in versions: 2014 - 2015, 2015 - 2022, 2022 - 2024, 2024 and beyond (current))
7712030: Access Mathematics Grade 2 (Specifically in versions: 2014 - 2015, 2015 - 2018, 2018 - 2022, 2022 and beyond (current))
5012005: Foundational Skills in Mathematics K-2 (Specifically in versions: 2019 - 2022, 2022 - 2024, 2024 and beyond (current))

Related Access Points

Alternate version of this benchmark for students with significant cognitive disabilities.
MA.2.M.1.AP.2: Measure the lengths of two objects using the same unit (i.e., inch, foot, yard) and determine the difference between their measurements.

Related Resources

Vetted resources educators can use to teach the concepts and skills in this benchmark.

Formative Assessments

How Much Longer?:

Students are asked to determine how many inches longer one line segment is than another.

Type: Formative Assessment

Dragonflies and Grasshoppers:

Students shown images of a grasshopper and a dragonfly and are asked to determine how much longer one is than the other.

Type: Formative Assessment

Walking Ants:

Students are shown the paths that two different ants took and are asked to determine how much longer one path is than the other.

Type: Formative Assessment

Comparing Zigzag Segments:

Students are shown a zigzag figure and are asked to determine how much longer the longest segment is than the shortest.

Type: Formative Assessment

Lesson Plans

Measure Both and Find their Difference:

Students will measure the lengths of two objects to the nearest inch and determine the difference in the objects' lengths.

Type: Lesson Plan

If the Shoe Fits...:

In this lesson, students will create line plots based on linear measurements that they collect while participating in the practice of scientific inquiry.

Type: Lesson Plan

What's the difference?:

This lesson is designed for students who already have a basic understanding of how to measure using rulers, yardsticks, or meter sticks. Students will first use given measurements of buildings to determine the difference between two objects’ lengths. Then, students will use their own measurement data to determine the difference between objects’ lengths.

Type: Lesson Plan

Comparing Inch by Inch:

This is a hands-on lesson that allows students to practice measuring different lengths of objects and writing equations to determine the difference between their lengths.

Type: Lesson Plan

Teaching Idea

Big as a Baby Whale-SeaWorld Classroom Activity:

In this activity, students will create life size chalk drawings of J.J. the gray whale to discover the size and growth rate of juvenile gray whales.

Type: Teaching Idea

MFAS Formative Assessments

Comparing Zigzag Segments:

Students are shown a zigzag figure and are asked to determine how much longer the longest segment is than the shortest.

Dragonflies and Grasshoppers:

Students shown images of a grasshopper and a dragonfly and are asked to determine how much longer one is than the other.

How Much Longer?:

Students are asked to determine how many inches longer one line segment is than another.

Walking Ants:

Students are shown the paths that two different ants took and are asked to determine how much longer one path is than the other.

Student Resources

Vetted resources students can use to learn the concepts and skills in this benchmark.

Parent Resources

Vetted resources caregivers can use to help students learn the concepts and skills in this benchmark.