Fractions - Subtract Fractions - Presentation

In the lesson centred on subtracting fractions, students are challenged to extend their understanding of fractions beyond addition to subtraction, particularly focusing on fractions with different denominators. The lesson revisits concepts from previous learning on adding fractions and encourages students to discuss whether the same principles apply to subtraction. A series of activities guide students through the process of subtracting fractions step by step. The first activity involves a clear, visual representation of subtracting fractions with like denominators, breaking down the process into manageable steps. Students are then asked to apply this method to subtract fractions with unlike denominators, such as 3/4 minus 1/8 and 6/7 minus 4/14, with the aim of reinforcing their understanding of the concept.

Further activities in the lesson include practical scenarios, such as comparing the remaining portions of pizza between two individuals, Zach and Esin, to contextualise the subtraction of fractions in real-life situations. A number line is used as a tool in another activity to visualise the subtraction of fractions, such as finding the difference between 2/10 and 6/5. This method is then applied to additional examples to ensure that students can confidently find the difference between various fractions. The lesson also incorporates reasoning tasks where students must identify the odd one out among several subtraction problems and solve for missing lengths in geometric problems, thereby testing their comprehension and application of the topic. Finally, independent work tasks encourage students to complete models for subtraction calculations and further reasoning exercises, solidifying their grasp of subtracting fractions.