When wrapping birthday or Christmas presents, the larger the gift, the more wrapping paper is needed. Here you can see the measurements of three birthday presents that Basil has bought for his wife.
a) What area of wrapping paper is needed to cover each of the three gifts?
Basil has a piece of wrapping paper that measures 50cm x 30cm.
c) Is Basil’s wrapping paper large enough to cover all of the gifts?
This video is a very practical example of surface area, and works well to consolidate learning in class. Students need to be able to recall areas of rectangles, circles and triangles, and also recognise markings on triangles to denote the type of triangle that it is. It normally takes students around 8 -10 minutes to solve this, although it sometimes works to split the class into groups, each group handling one of the shapes. A similar video exists without the cylinder for students who have not yet mastered circles.
Teachers could extend the learning by considering:
- Create an additional gift which combines different units – mm, cm or metres and ask students to work out the surface area of that gift.
- Provide the area of an alternate piece of wrapping paper in metres squared, and ask students if that piece of paper would wrap all the gifts. This leads nicely into conversion of squared or cubed units.