Abstract:

Teaching geometric transformations and keeping students’ interest is a task that highly demands teachers to design very carefully the activities to be performed in the classroom. In our days, activities involving technologies use to attract students’ interest. Students can understand more deeply the concepts of reflection or translation if they use them in a practical work. For that it is possible to use dynamic geometry software, such as GeoGebra, and ask students to complete some drawings using geometric transformations. For instance, if a teacher gives their students “half a house” that was built in a referential, using geometric shapes, such as squares and triangles, students can be asked to complete the house by symmetry on the vertical axe. The next step is to ask students to produce themselves “half-objects” and then ask their colleagues to complete the object by reflection along horizontal or vertical axe or either by reflection along a straight line.

Another idea is to construct a pine-tree using triangles and rectangles and then using translation, transform this pine-tree to a dense pinewood. When the pinewood is completed it is possible to suggest other objects like clouds or flowers, that can be made up with geometric shapes and that, by several translations can be transform in a cloudy sky or a garden.

In this paper we present some concrete ideas and activities designed to be used in classroom and we give account of students’ reactions.

Keywords:

Dynamic geometry software, Geometric transformations.