An exploration of multimedia programs in the teaching of photosynthesis

This thesis investigates the effectiveness of two multimedia programs in delivering an understanding of the light - dependent reaction of photosynthesis. One program, Cells and Energy, was adaptive, whilst the other, Photosynthesis Explorer, was interactive (a practical simulation). To inform the value of these different designs an empirical study was conducted. Ten pairs of participants were allocated to use one or other of the programs. During their use and with the researcher's support, members of each pair attempted to learn about the light-dependent reaction. Whilst doing so, audio and visual data were captured to provide information as to participants' and researcher's activities related to this learning process. Each participant's understanding was determined by matched pairs tests - as a pre-test and as immediate and delayed post-tests. The programs generated a highly significant difference (p Photosynthesis Explorer group took about three times as long to deliver this equivalent effect. By employing Laurillard's Discourse Model for evaluating events, which were recorded during the programs' use, this research provided evidence of the importance of feedback as scaffolding and support in delivering knowledge and understanding. The recorded, as well as test, data revealed misconceptions. Their effects on learning were complex as were cognitive conflict episodes arising from them, whose resolution was multifaceted

Towards a framework for the analysis of CSCL (computer supported co-operative learning) discourse

The thesis aims to develop a possible description of electronic discourse in CSCL\ud through a data-driven description of the linguistic behaviour and discourse strategies of 4\ud groups of postgraduate students engaged in an asynchronous CSCL task during-February\ud 2000 and February 2001.\ud The study develops an analytic framework for the coding of the messages. The\ud framework consists of three levels, with a default inheritance relationship between these\ud levels. The top level concerns the aim of the messages, identified within the broad\ud context of Levinson's Activity Type. The mid-level consists of the traditional\ud conversational analysis categories, with some minor adaptations to the CMC medium.\ud The third level is based on a neo-Gricean approach to utterance interpretation, with\ud special attention to Levinson's (2000) theory of generalised conversational implicature.\ud The analysis was conducted through intensive reading of the coded data to identify\ud categories of speaker behaviour. The categories were then collated to address the research\ud question. 19 categories were identified, covering 4 aspects of discourse behaviour.\ud As an additional test of the discourse analysis framework, the coded output was used as\ud data for a separate theory-driven question. The question was to seek evidence of\ud behaviour typical of the iterative dialogue that characterises Laurillard's (2002) model of\ud learning through conversational dialogue.\ud The research study found that the majority of the discourse categories identified by the\ud framework are valid, although some need to be refined. In particular, 4 basic message\ud structure types, and distinctive patterns in the use of indirect and direct forms of\ud expression are clearly identified in this data. There are also clear indicators of strategies\ud used to maintain cohesion and coherence. In the test case, the coded data was used to\ud identify six types of critical learning behaviour that are broadly consistent with\ud Laurillard's model of learning