Ratio - Using Scale Factors - Presentation

In a series of engaging lessons on the concept of scale factors, Year 6 students delve into the mathematical principles of enlarging shapes. The lessons begin with a discussion prompting students to consider what it means to 'enlarge' something and to define a 'scale factor', encouraging them to draw on their previous encounters with the term 'factor'. The initial activities involve practical tasks where students are instructed to copy rectangles onto squared paper and then redraw them at various enlarged sizes, specifically double, triple, and quintuple their original dimensions. This hands-on approach helps to cement the students' understanding of how shapes can be proportionally increased in size.

Further activities require the students to apply scale factors to different shapes, such as enlarging them by factors of two and three, and to reflect on how squared paper assists in this process. The lessons also include reasoning tasks where students enlarge a given rectangle and compare its perimeter, area, and angles before and after scaling. Through these exercises, students discover that while the perimeter and area are affected by the scaling process, the angles remain unchanged. Independent work reinforces the concept, with students enlarging rectangles and triangles by specific scale factors and then examining the changes in perimeter and area, thus deepening their understanding of ratio and proportion in the context of geometry.