Improving teaching and learning for chemical equilibrium and acids and bases in Year 12 chemistry : a thesis submitted in partial fulfilment of the requirements for the degree of MAster of Education at Massey University, Palmerston North, New Zealand
The aims of this action research study were to develop, implement, and test the efficacy of four strategies designed to improve the teaching and learning of chemical equilibrium and acids and bases in year 12 chemistry. The study took place in a New Zealand secondary school, with two year 12 chemistry teachers and fifteen randomly selected students taking part. Semi-structured interviews used to elicit students' pre-teaching mental models of concepts within chemical equilibrium and acids and bases revealed a range of misconceptions and a limited ability to represent the sub-microscopic level of chemistry concepts. Teachers then used information from the interviews to inform the planning of lessons for each topic. The new teaching strategies employed by the teachers centred around Johnstone's three levels of chemistry; using a macroscopic, sub-microscopic, symbolic sequence during teacher explanations of concepts. Particular emphasis was placed on modelling the sub-microscopic level of each concept with magnetic cardboard dots and student role plays. The action research process allows teachers to improve their own understandings and teaching practices through cycles of planning, action, observation and reflection. Although the action research methodology used here was new to both teachers at the start of the study, it provided a useful structure in which to trial the new strategies. Reflection in action research is an opportunity for teachers to reflect on, and evaluate, the effects of their action. This study demonstrates that understanding of concepts within chemical equilibrium and acids and bases is significantly improved if the sub-microscopic level of concepts is represented. For the students in this study, the preferred method of representing the sub-microscopic level was with cardboard dots rather than student role plays. Ideally, students themselves need to practise representing the sub-microscopic level with cardboard dots or other concrete models if they are to gain better understanding of the sub-microscopic level.