Development of preservice teachers' content knowledge in geometrical transformations: A teaching experiment

International audienceGeometrical transformations is one of the basic learning domains of geometry and mathematics teachers' content knowledge has a big impact on construction of middle school students' knowledge in this context. For this reason, the purpose of this study was to research preservice mathematics teachers' content knowledge and to design a teaching process including an appropriate scaffolding tool to provide participants to shift from informal thinking to formal thinking on geometrical transformations. According to results it was revealed that acetate could be designed as an effective scaffolding tool for developing the view of " bijective function " , exploring relations, and making generalizations regarding the geometric transformations