Choosing the fraction model
As explained in Big Ideas, a comprehensive understanding of fractions includes understanding the different meanings for fractions.
Different meanings for fractions are associated with different representations. For example, the part-whole meaning is usually illustrated with the area of a shape partitioned into equal parts.
Students are expected to model fractions in a variety of ways because this indicates understanding of the various meanings for fractions. For example, locating fractions on a number line requires one way of thinking about fractions, while folding paper shapes to show fractions requires a different way of thinking.
Therefore, when designing assessment tasks, the choice of fraction model is an important consideration.
Designing Assessment Tasks: Choosing the Fraction Model provides a list of some of the common models for fractions and examples of tasks that suggest or demand the use of that particular model.