In this study, the researcher sought to understand why teachers of Physical Sciences participate in the South African 'Eskom Expo for Young Scientists'. This was analysed in terms of the educational significance that they perceive the science fair to offer, what sustains their participation over a long period of time, and the extent to which Expo participation provides an opportunity for professional development. The educational significance of the Expo was established in terms of its contribution to the Professional Identity of teachers, and was related to the roles (organiser, mentor and judge) of participation in science fairs.
The sampling employed in the study was both purposive and convenience-based in nature. Only schools participating regularly (at least five times in the past ten years) in the long running (since 1980) of the 'Expo for Young Scientists' (Northern Gauteng Region) were selected. Five urban public high schools and ten teachers of the school subject "Physical Sciences" were identified to participate in this study. Face-to-face semi-structured interviews were conducted with two teachers from each school in this QUAL-quan research approach. The interview transcripts were subjected to a thematic analysis, where after the points raised by the teachers were clustered into categories and related to sub-themes and themes according to the educational significance for teachers, the benefits and drawbacks for learners, teachers' Professional Identity, and reasons for sustained participation.
Many researchers regard science fairs as one of the better ways to enhance science education. Globally, science fairs have been taking place for more than 30 years and are thought to have educational value for both science teachers and learners. These science fairs provide a context for the development and application of scientific investigation and research skills. This research employed the model of Beijaard, Meijer and Verloop (2004) to characterise teachers' Professional Identity (professional knowledge, attitudes, beliefs, norms and values, and emotions). The researcher also employed Ajzen's (1991) Theory of Planned Behaviour to understand why teachers take part and sustain their involvement in the Expo, be it at school or regional level. The major focus was thus on the benefits for teachers as perceived by them, with some contextualisation of the educational benefits and potential drawbacks for learners, while the literature to date has largely reported on the benefits for learners.
This study has found that expos provide sustainable educational significance in terms of professional development for teachers, and enhance aspects of their Professional Identity, such as contributing to pedagogical knowledge, pedagogical content knowledge, as well as scientific procedural and declarative or factual knowledge. Their self-efficacy beliefs are strengthened, positive attitudes are developed, and strategies of inquiry based learning and effective methodological instructions in science education, which contributes to their teaching. Learners gain knowledge of science through reading and investigations, and also learn more of the nature of science. Teachers' values (and those of their schools) are reflected when their emotions are lifted in sharing learners' achievements in the science Expo. Teachers learn both from their engagement with learners, but also through networking opportunities with fellow teachers. The consequent enhancement of Professional Identity contributes to the sustainability of their participation in the Expo.
Although this research focused on teachers of Physical Sciences, learners in the Expo are guided on projects ranging from biology and environmental sciences, engineering and design, information technology to psychology, and various social sciences beyond the physical sciences. The teachers who guide the subjects related to these fields possibly have similar experiences, thus extending investigations to such teachers would surely provide a richer set of insights. Teachers who do not sustain their participation did not form part of the research, but their experiences and perceptions were included to further enrich the nature of the findings. It is recommended that the opportunity for professional development that is provided by teachers' participation in such school level investigation science fairs be acknowledged and promoted by schools and fair organisers. They can do this by continuing to extend the range of teachers who are encouraged to be involved in such science fairs.