Use of visual aids in teaching science: Practices and attitudes of secondary science teachers

Visual aids are generally believed to be able to enhance learning and support teacher based instructions. In the words of Heinich, Molenda and Russell (1993), they can"help teachers become creative managers of the learning experiences rather than merely dispensers of information." However, there has so far been very limited research on the use of visual aids in Hong Kong schools. This paper presents the findings of a questionnaire survey on the use of visual aids by science teachers in local secondary schools. The aims of the survey are to study the attitudes and actual practices of science teachers in using visual aids in teaching secondary science subjects and their receptivity to innovative visual aids, and to identify the factors which influence their attitudes and actual practices. Altogether 120 science teachers from over 30 secondary schools responded to the survey. The target schools were selected by random sampling from all Hong Kong schools and from schools placed with student teachers of the Hong Kong Institute of Education for teaching practice. For each school sampled, 4 science teachers teaching Integrated Science, Chemistry, Biology and Physics respectively were selected as respondents. The data collected from the questionnaire survey were subject to statistical analysis using SPSS to show the frequency of use of different types of visual aids across different science subjects, the teachers' perception of the benefits and constraints of using visual aids in teaching science, and the relationships among these and other variables like teaching experience as identified in the survey. The findings reveal that although the use of chalk and board is still the rule in science classes, other conventional visual aids such as overhead projector, video and models are utilized to a fairly wide extent with variations in the types of aids used across different science subjects. However, more advanced visual technology such as multimedia and three-dimensional visualization techniques are rarely used for teaching science. The attitudes of the respondents to use of visual aids in teaching science were found to be positive in general. Visual aids are perceived by respondents to be effective in the teaching and learning of science, particularly in arousing interest, explaining scientific facts and in illustrating scientific principles, laws and theories. The main reason for rarely or not using visual aids as cited by the respondents is related more to the unavailability of appropriate visual aids rather than their being ineffective as a teaching or learning tool. Lastly, the respondents identified a range of scientific concepts in different science subjects which they find difficult to teach without employing visual aids. Those findings will form the cornerstone for conducting a large-scale research project, entitled "Application of Three-Dimensional Visualization Techniques in Science Education" as supported by the Hong Kong Institute of Education.