Comparing B
Comparing Fractions
Compare familiar fraction quantities with and without benchmark referents
Understanding a fraction as a number (a quantity) and using multiple strategies to compare familiar fraction quantities helps students compare fractions beyond merely using common denominators.
Background
Comparing and ordering fractions allows students to develop a sense of fraction as quantity, as well as a sense of the size of a fraction, both necessary prior knowledge components for understanding fraction operations (Johanning, 2011).
Comparing and ordering fractions with different fractional units (or denominators) leads students to identify the need for equivalent fractions. When students determine an equivalent fraction they are changing the unit of measure by either splitting or merging the partitions of the original fraction. The following illustration demonstrates these concepts using an area model:
Splitting to determine an equivalent fraction for 2⁄3
Merging to determine an equivalent fraction for 6⁄8
The exploration of equivalence allows students to develop an understanding of equivalent fractions as simply being a different way of naming the same quantity; it also supports them in viewing the fraction as a numeric value. A solid understanding of equivalence helps students with fractions operations, especially addition and subtraction.
References:
Johanning, D. I. (2011). Estimation's role in calculations with fractions. Mathematics Teaching In the Middle School, 17(2), 96-102.
Tasks
Familiar Fractions and Benchmarks Comparisons
This is a set of prompts consisting of purposefully paired fractions to elicit the use of various strategies. The prompts may be used on different occasions for either Minds-On activities or for Action tasks depending on student readiness. Repeated practice and exploration in making comparisons between fractions will deepen student understanding.
Additional Prompts
These tasks emerged out of the fraction research. Teachers may wish to use them as diagnostic or summative assessments, exit cards, number talk prompts, or additional practice questions. By considering both the specifics of the cell and student use of purposeful models, teachers can support students in acquiring a strong conceptual understanding.