The teacher shows the students a homemade 40 cm 3D teddy bear. The teacher explains that the students will be creating their own teddy bear from the pattern and materials provided. ‘However, there is one catch, the teddy bear pattern we have only makes a 30cm tall teddy bear and we want a 40 cm tall teddy bear. The challenge is for you to develop a method to create the larger teddy bear based on this pattern.’
The students discuss a variety of methods for enlarging the teddy bear. The following are strategies observed or suggested during the trialling of this task.
A couple of students used the data projector and zoom function in 'Word' to adjust the teddy bear pattern until they found the correct ratio. They redrew the teddy bear onto a grid placed on the enlarged image.
Some students attempted to enlarge the pattern by simply tracing the shapes about 1cm outside the original grid to make them bigger. This method is not to scale.
Some students suggested photocopying the pattern and using the enlarge function set at 133%.
Another suggestion was to create larger graph paper in a ratio of 3:4 and copy each part onto the new graph paper.
The students calculated that for every 3 cells on the grid they needed 4 cells on a new grid. They calculated where the widest and narrowest point of a body part should be and placed a dot at that point on the new graph paper. The students then drew in the rough shape of the larger body part onto the new graph paper. This enlarged template was transferred to stiff cardboard. The material was traced using the new template.
The task is undertaken throughout the course of the unit. During this time, students share their strategies with the class to seek feedback to further refine the enlarging process. Students use any spare time during the day or as a part of their homework to complete the sewing.
The students present their completed teddy bears and share their methods for scaling the pattern to create a 40cm teddy bear.