Abstract
The purpose of this study was to examine topic-specific nature of pedagogical content knowledge (PCK). Since 1986, the introduction of PCK, scholars have studied how PCK develops, sources of it, and how components of PCK interplay with each other. From the acknowledged research, it has been asserted that PCK is a topic-specific construct (Loughran, Mulhall, & Berry, 2004; van Driel, Verloop & De Vos, 1998). However, research has not been shown how PCK is topic-specific and how teachers transform SMK of different topics into PCK for teaching them (Abell, 2008; van Driel et al., 1998). Therefore, the literature has clearly identified the need for more topic-specific PCK research within the complexity of the classroom to determine how teachers’ use their PCK in transforming their SMK into pedagogically powerful representations to support student learning (Abell, 2008; van Driel et al., 1998). Related to this point, Loughran et al., (2004) highlighted the scarcity of concrete examples of teachers’ PCK. Therefore, the current research is supposed to provide valuable information about experienced teachers’ PCK and how they use their PCK in teaching for particular topics because PCK is specific to topic (van Driel, et al., 1998).
In this study, two experienced chemistry teachers’ PCK was examined in electrochemistry and radioactivity topics. To capture participants’ PCK, all PCK components suggested in Magnusson, Borko, and Krajcik’s (1999) PCK model were studied. To get deep and rich answers to research questions asked, qualitative methodology was used. To get better information about experienced teachers’ PCK and its nature, teachers who had a potential to provide rich data were selected (Patton, 2002). Data were gathered through card-sorting activity, Content Representation (CoRe) (Loughran et al., 2004), semi-structured interviews, classroom observations, and field notes. Figure 1 shows the data collection timeline.
Figure 1. Dissertation data collection timeline
In terms of the topics, electrochemistry and radioactivity were studied because these two topics have not been studied in terms of topic-specific PCK yet. Additionally, research has provided misconceptions and difficulties that students have in electrochemistry (Sanger & Greenbowe, 1997) and in radioactivity (Nakiboğlu & Tekin, 2006). Moreover, two topics have to be at the same grade level due to the fact that orientation to science teaching component is grade specific. Additionally, the topics should not be related to each other because the purpose of the study was to compare PCK in different topics. Therefore, from the 11th grade curriculum in Turkey, electrochemistry and radioactivity were chosen to examine PCK in different topics.
Results revealed that participants had two types of PCK, namely, PCK A for teaching electrochemistry and PCK B for teaching radioactivity. PCK A included content-based and teacher-centered instruction, many links to other topics in chemistry and in physics. The assessment was coherent which included different types of assessment strategies used at the beginning, during, and at the end of teaching. In PCK B, it was less teacher-centered. The link to other topics was limited. Additionally, teachers used fragmented assessment and were less knowledgeable about learners’ difficulties and misconceptions in radioactivity than they were in electrochemistry. Differences between PCK A and B may be related to nature of the topics. Learners need to have much pre-requisite knowledge both from chemistry and physics to learn electrochemistry. Also, there are more concepts in electrochemistry than there are in radioactivity. It seems that when teachers have to focus on more concepts to teach, they may have a tendency to teach more-teacher centered to save time. Teacher education programs should focus on topic-specific nature of PCK and provide topic-specific training to teachers.
References
Abell, S. (2008). Twenty years later: Does pedagogical content knowledge remain a useful idea? International Journal of Science Education, 30, 1405-1416.
Loughran, J., Mulhall, P., & Berry, A. (2004). In search of pedagogical content knowledge I science: Developing ways of articulating and documenting professional practice. Journal of Research in Science Teaching, 41, 370-391.
Magnusson, S., Krajcik, J., & Borko, H. (1999). Nature, sources and development of pedagogical content knowledge for science teaching. In J. Gess-Newsome & N. G. Lederman (Eds.), Examining pedagogical content knowledge: The construct and its implications for science education (pp. 95-132). Boston: Kluwer.
Nakiboğlu, C., Tekin, B. B. (2006). Identifying students’ misconceptions about nuclear chemistry. A study of Turkish high school students. Journal of Chemical Education, 83(11), 1712-1718.
Patton, M. Q. (2002). Qualitative evaluation and research methods (3rd ed.). Thousand Oaks, CA: Sage.
Sanger, M. J. & Greenbowe, T. J. (1997). Common student misconceptions in electrochemistry: Galvanic, electrolytic, and concentration cells. Journal of Research in Science Teaching, 34, 377-398.
Shulman, L. S. (1986). Those who understand: Knowledge growth in teaching, Educational Researcher, 15, 4-14.
Van Driel, J. H., Verloop, N., & de Vos, W. (1998). Developing science teachers’ pedagogical content knowledge. Journal of Research in Science Teaching, 35, 673-695.
Thesis full reference:
Aydin, S. (2012). Examination of chemistry teachers’ topic-specific nature of pedagogical content knowledge in electrochemistry and radioactivity, Unpublished Doctoral Dissertation, Graduate School of Natural and Applied Sciences, Middle East Technical University, Ankara, Turkey.
Corespondence
Sevgi Aydin
Middle East Technical University, College of Education, Office: 209, 06800, ANKARA-TURKEY.
Tel: (0090) 312 210 40 86
E-mail: sevgi.aydin45@hotmail.com, or: sevgi.aydin45@gmail.com
