Fractions - Subtract fractions - Presentation

The lesson on subtracting fractions is designed to reinforce the understanding of different subtraction structures, such as taking away, finding the difference, and partitioning. Students are encouraged to discuss and provide examples of each structure using whole numbers. The lesson includes a variety of activities where students apply these concepts to fractions. In the first activity, students are presented with a scenario involving Malachi eating a chocolate bar, and they are tasked with filling in the missing fractions to show the subtraction process. This practical example helps to contextualize the abstract concept of fraction subtraction for the learners.

Subsequent activities involve using visual models to aid in the subtraction of fractions. For instance, students are asked to use fraction models to subtract fractions with different denominators, such as 5/8 from 5/10 and 6/6 from 2/6. These models offer a concrete representation of the fractions, making it easier for students to grasp the subtraction process. The lesson also includes part-whole models where students complete the models to reflect the subtraction taking place. The final activities challenge students to reason mathematically, by completing missing fractions in a sequence and explaining the methods used by fictional students, Zach and Leanna, to arrive at their answers. The lesson culminates with independent work, where students use bar models to solve calculations, draw their own models, and find the difference between fractions, further solidifying their understanding of fraction subtraction.