It is mooted that the implementation of computer technology in science laboratories will enhance students' learning as a result of overcoming delays in processing results, providing simultaneous multiple measurements, and, facilitating observation of phenomena in multiple representations (e.g. graphs and tables). Consequently, microcomputers are being increasingly used in school chemistry laboratories for data logging, analysis of data, interaction with the student in the analysis of that data, and the development of understanding of phenomena. This paper reports on a study where the promise of using microcomputers to enhance students' understanding was not fulfilled. Factors affecting the students' and teacher's use of the microcomputer, and consequent less-than-expected levels of student learning, included their beliefs about teaching and learning and their beliefs about the role of practical work in the chemistry course. Suggestions for bridging the gap between the myths associated with the use of such technology and the reality of contemporary senior science classes are proposed.