Exploring PCK in the process of teaching radioactivity : strategies employed by Lesotho physics teachers
Hlaela-Mohlouoa, Nthoesele Melahlohonolo
Some teachers perceive radioactivity as a difficult topic to teach due to its abstract nature. This topic is included at senior secondary level in the combined science syllabus and is taught for the first time to learners who study physics. This study was carried out to make explicit two teachers‟ PCK (pedagogical content knowledge) on teaching radioactivity and to investigate the role of experience in the PCK of the two physics teachers. Mr Victor had 19 years while Ms Grace had 3 years of teaching experience at the time of this study. I used pre-observation interviews, video recorded classroom observations, field notes, diagnostic test and post observation discussions as data collection methods. The data was processed using Content Representation (CoRe) and Pedagogical and Professional experience Repertoires (PaP-eRs) as methodological tools to document and portray the teachers‟ PCK in teaching radioactivity. The CoRe that helped to give insights into how the two teachers framed the topic of radioactivity was constructed from the pre-observation interview data and video recorded classroom observations transcripts. The PaP-eRs were constructed from video recorded classroom observation transcripts and field notes and they were narratives of the classroom practice of the teachers. I also used the model of Rollnick et al. (2008) to analyse data. This study has not come out clear on total absence of PCK in Ms Grace as a beginning teacher. There are some very good aspects that have been demonstrated by Ms Grace that have not been demonstrated by Mr Victor with reference to the topic specific strategies. Both teachers showed that they had a repertoire of teaching strategies to suit their teaching context. As Mr Victor did, Ms Grace as a beginning teacher employed some effective strategies to suit her learning demands and this indicated that the teachers were able to manifest their well developed PCK when the four knowledge domains that generate teachers‟ PCK were integrated. Pertaining to knowledge of assessment and curricular saliency, there were no observable PCK differences between the two teachers. The study showed that Mr Victor used a variety of representations to teach radioactivity while Ms Grace‟s use of representations was more limited. Through the use of the model of Rollnick et al. (2008), I indicated that Mr Victor had well developed PCK while Ms Grace‟s was less developed with regard to representations used. The manifested knowledge of various representations for Mr Victor was produced from the integrated knowledge of the four knowledge domains in the model. The diagnostic test revealed that Mr Victor had required subject matter knowledge to teach within the syllabus he was teaching. Ms Grace‟s subject matter knowledge seemed fragile. The existence of PCK in Ms Grace implies that both experienced and beginning teachers can learn from each other to improve their teaching.
M.Sc., Faculty of Science, University of the Witwatersrand, 2011
Science teachers, Science (study and teaching), Science teachers, training of