Leung K C Issic , Lin Ding , Allen Yuk Lun Leung , Ngai Ying Wong
DOI: JANT Vol.18(No.3) 171-185, 2014
Mathematically deductive reasoning skill is one of the major learning objectives stated in senior secondary curriculum (CDC & HKEAA, 2007, page 15). Ironically, student performance during routine assessments on geometric reasoning, such as proving geometric propositions and justifying geometric properties, is far below teacher expectations. One might argue that this is caused by teachers` lack of relevant subject content knowledge. However, recent research findings have revealed that teachers` knowledge of teaching (e.g., Ball et al., 2009) and their deductive reasoning skills also play a crucial role in student learning. Prior to a comprehensive investigation on teacher competency, we use a case study to investigate teachers` knowledge competency on how to teach their students to mathematically argue that, for example, two triangles are congruent. Deductive rea-soning skill is essential to geometry. The initial findings indicate that both subject and pedagogical content knowledge are essential for effectively teaching this challenging topic. We conclude our study by suggesting a method that teachers can use to further improve their teaching effectiveness.