Enhancing pedagogical content knowledge in a collaborative school-based professional development program for inquiry-based science teaching

As this study involved only two schools and ten teachers, it is not possible to generalize its findings to other school contexts. Nevertheless, it has generated a number of interesting findings about the impact and challenges of professional development that emphasizes university-school collaboration and the development of teachers’ PCK for inquiry-based teaching.

The findings of the two cases indicate that these teachers were still concerned about their SMK, although their responses on the post-study questionnaire were more positive. It would be reasonable to conclude that they developed a better understanding of the SMK through coaching and reflecting upon their own misconceptions. However, several issues arise from the teachers’ persistent sense of inadequacy in handling students’ questions. First, this lack of confidence meant they dared not venture too far from the planned activities. Second, they tended to interpret the students’ level of understanding through the lens of their own SMK. The concepts that the teachers themselves found difficult were perceived as being too demanding for the students. Third, the teachers made use of different teaching strategies to overcome their lack of confidence to a certain extent. For instance, some teachers videotaped experiments to substitute for hands-on activities. This is consistent with research findings (Smith, 1999; van Driel et al., 1998) that teachers tend to use general pedagogical knowledge to compensate for inadequacy in SMK.

The findings also have implications for the type of SMK that primary teachers need to be able to teach science through inquiry: SMK should be understood not only in terms of scientific concepts, but also in terms of the nature of scientific inquiry. This aspect of SMK will allow teachers to guide students through the inquiry process, including formulating hypotheses, designing experiments to obtain evidence, and making explanations based on that evidence. Little evidence of this type of SMK was found among the teachers in this study.

The analysis of the pre-lesson test results and lesson episodes challenged the teachers’ perceptions of students’ understanding of the topics and reasoning ability. Such cognitive dissonance on the part of the teachers could stimulate a reassessment of their existing knowledge of learners.

The findings also shed light on the rather elusive nature of PCK. First, teachers’ PCK is continually expanding and developing, based on their reflections on their teaching experiences. In the two case studies presented here, the teachers’ PCK developed throughout the lesson, as they received feedback from the students on their existing understanding of the topic and on the effectiveness of the teaching strategies so far employed. Second, PCK for scientific inquiry is both contextual and generic. It is context-dependent, because the nature of the topic and the learning context inevitably influence the inquiry strategies the teacher employs. It also contains elements that could be generalized to different inquiry situations, including the design of student-centered activities for the observation of natural phenomena, and the identification of questions to investigate. Third, PCK is idiosyncratic; that is, it contains many elements that are characteristic of the individual teacher. PCK varies with teachers’ SMK, their perception of their students’ level of understanding and reasoning ability, their teaching style, and the teaching approach considered to be suitable for particular students. For instance, in the inquiry into the existence of air, George employed carefully structured experimental activities to lead the students to discover this existence, whereas Nancy utilized students’ everyday experiences with air.