Clarifications
Clarification 1: Instruction includes seeing rulers and tape measures as number lines.Clarification 2: Instruction focuses on recognizing that when an object is measured in two different units, fewer of the larger units are required. When comparing measurements of the same object in different units, measurement conversions are not expected.
Clarification 3: When estimating the size of an object, a comparison with an object of known size can be used.
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 build instruction from grade 1 to include additional U.S. customary and metric units. Students will both estimate and measure objects in various units and are expected to select an appropriate measurement tool.- Instruction includes helping students identify benchmark measurement references.
- Instruction includes helping students connect the concept of a number line to linear measurement tools such as rulers and tape measures.
Common Misconceptions or Errors
- Students may misalign the ruler with the object and measure an object from 1 instead of 0.
- Students may count all marks, not just the whole-unit marks, when labeling a ruler.
- Students may not have a clear concept of the approximate length of an inch, a foot, a centimeter or a meter.
Strategies to Support Tiered Instruction
- Instruction includes modeling how to measure an object and guiding students to notice that the object’s measurement does not change if the object is placed further down the ruler.
- For example, modeling may include identifying the end points of an object and lining the end point with the zero mark of the ruler. Note that often the “zero” mark is not labeled and may be the end of the ruler or on the very first tick mark depending on the ruler. The teacher states the correct measurement and then as students watch, move the object down the ruler and ask, “Does the object’s measurement change if its end point lines up with a different number?”
- Instruction includes directing students to make connections between their world and measurements of inch, foot, centimeter and meter. Students discuss these relationships, draw pictures and write labels that can be used as a reference to help them remember the different length units and their approximate sizes.
- For example, students can use index cards to draw examples of each length unit relationship. Multiple cards can be made so that students can sort, do a memory match, or combined to create a mini booklet.
Instructional Tasks
Instructional Task 1 (MTR.4.1, MTR.6.1)
As a class, determine several classroom objects whose lengths can be measured (e.g., pencil, book, desk, glue stick, etc.).- Part A. Before measuring, select an appropriate tool and estimate the number of units.
- Part B. Compare their estimates to the actual measurement. Include a comparison of the number of units based on the tool selected.
Instructional Items
Instructional Item 1
Nancy measured her index card using a ruler. She thinks the index card is about 9 cm. long. Is Nancy’s work correct? Explain why or why not.*The strategies, tasks and items included in the B1G-M are examples and should not be considered comprehensive
Related Courses
Related Access Points
Related Resources
Formative Assessments
Lesson Plans
Original Student Tutorial
Professional Development
Teaching Idea
MFAS Formative Assessments
Students measure the length of a line segment twice and are given an opportunity to explain why the line segment measures in fewer meters than centimeters.
Students are asked to estimate the length of a line segment in centimeters.
Students measure the length of a line twice and are given an opportunity to explain why the line measures in fewer feet than inches.
Students are given the length of an alligator in both feet and yards and are asked to explain why the measure given in feet is greater than the measure given in yards.
Students measure the length of a line segment twice, once using inches and again using centimeters, and are asked to explain why the two measures are different.
Students use a ruler to measure a 17 inch segment to the nearest inch.
Students use a ruler or yardstick to measure a length to the nearest foot.
Students use a ruler to measure one segment to the nearest inch and one segment to the nearest centimeter.
Original Student Tutorials Mathematics - Grades K-5
A 6 foot bug? No way! Learn how to estimate length using inches, feet and yards by using objects around you in this interactive tutorial.
Student Resources
Original Student Tutorial
A 6 foot bug? No way! Learn how to estimate length using inches, feet and yards by using objects around you in this interactive tutorial.
Type: Original Student Tutorial