Human-Sized Number Lines: Let’s Compare Fractions

  • Description
  • Files

What we like about this lesson

Mathematically:

  • Addresses standards 4.NF.A.2, 4.MD.A, 4.MD.A.2
  • Allows students to see fraction equivalence with a large visual model
  • Promotes coherence by highlighting prior knowledge and pointing to the mathematics that will be built from these ideas
  • Encourages students to use appropriate tools strategically (MP.5) (see additional thoughts below)
  • Requires students' use of precise grade-appropriate mathematical language (MP.6)
  • Reinforces that fractional comparisons are valid only when referring to the same whole
  • Uses fractions greater than 1 to support students’ understanding of fractions as numbers (e.g., 3/2, 5/3)

In the classroom:

  • Captures student attention by using an engaging context
  • Gives formal and informal opportunities for teachers to check for understanding
  • Provides robust opportunities for students to discuss mathematical concepts; includes guiding questions for teachers to use to facilitate discussion

  • Making the Shifts

    How does this lesson exemplify the instructional Shifts required by CCSSM?

    Focus Belongs to the major work of fourth grade
    Coherence  Builds on key understandings of fractions as numbers (3.NF.A), equivalence and comparing fractions with same numerators and denominators from grade 3.
    Rigor

    Conceptual Understanding: primary in this lesson

    Procedural Skill and Fluency: not addressed  in this lesson

    Application:not addressed in this lesson
  • Additional Thoughts

    This lesson would best fit early in the fraction unit of fourth grade. It is not intended for students to meet the full expectations of the targeted grade-level standards through only this selected lesson. The content in the lesson builds on grade 3 work of comparing fractions with same numerators and denominators and extends to comparing fractions with unlike numerators and denominators. The lesson lays a strong foundation for students to extend fraction equivalence and ordering from grade 3 and builds on students’ understanding of fractions as numbers. The use of the number line supports students in their continued development of fraction understanding. Solving problems posed involving measurement and representing length by using the number line supports coherence within the lesson by connecting supporting work to the major work of the lesson. .

    The format of the lesson has some interesting aspects to highlight. It is highly engaging and active, and meant to spark conversation between teacher and students as well as and students with one another. It is important to note that within the individual lesson the selection of lengths are deliberate and purposeful..  Not only are grade level content constraints adhered to, but careful attention is paid to the number line length (8 feet for length of 4/2 , 48 inches for length of 2/2) and denominators (2, 3, 4, 6, 8, 12).  It is important that the teacher checks student partitions to ensure student number lines are precise enough to move forward with the lesson.

    This lesson allows students to use their understanding of fraction equivalence to compare fractions with unlike numerators and unlike denominators, and students can rewrite fractions to show equivalence using visual models.  This individual lesson encourages students to use appropriate tools strategically in order to partition their number lines as closely as possible to the exact location (MP.5).  Teacher questions allow for student responses that attend to the precise language of fraction comparison and equivalence (MP.6).  For more insight on the grade-level concepts addressed in this lesson, read pages 6-7 of the progression document, Number and Operations- Fraction, 3-5.

Supplemental Resources