Abstract:

Previous research has compared the effects of computer-assisted instruction with those of traditional, teacher directed exposition. However , the results have been too mixed to permit any firm conclusions that can encourage new pedagogic interventions. The present paper evaluated the efficacy of these two instructional methods using a sample of 64 students (30 females, 34 males) randomly selected from a population of about 200 black students that were enrolled in a one year foundation program offered by the university of Pretoria in South Africa. In the country there has been a pressing need for educational institutions to redress the racial inequalities of the past in relation to access to mathematics and science based fields. This has underpinned the emergence of foundation year programs at various South African universities, providing highly enriched learning environments to black students coming from disadvantaged school and home backgrounds but showing a great potential for pursuing further studies in these fields. Foundation year programs exist as interfaces between secondary and tertiary education and embrace a vigorous academic preparation that lasts a full year. This is done to prevent deficiencies of prior secondary schooling, where learning by rote is rife and causes serious problems at tertiary level. The experimental research design was applied at the beginning and at the end of the first semester of the 2007 academic year as pre-test and post-test measures respectively. The students were randomly divided into a control group of 32 students that received traditional teaching in the form of lectures and prescribed textbooks in their usual classroom. The remaining experimental group were exposed to CD ROM based learning in a biology laboratory equipped with a computer and a data projector for large group viewing. The CD ROM was packaged with numerous computer graphics, animations, simulations, audio files, digital video clips and interactive diagrams. Both groups were handled by one teacher to ensure consistency in every action taken. Demographic data that were controlled included gender and previous biology knowledge. The instrument used to measure student performance involved 40 multiple-choice questions on selected biology topics that represented very abstract and difficult content. These included the cell cycle, electron transport systems, DNA replication, protein synthesis, enzyme action and so on. Statistical t-testing was applied in order to determine whether the performance of the two groups differed significantly. Concerning the pre-test mean scores, there was no significant difference between the experimental and control groups (p>0.05). With regard to post-test scores, the experimental group significantly outscored the control group (p<0.05). Performance slightly favoured boys and those with matric biology, but the difference fell short of statistical significance. In general, these findings affirm some of the previous findings that computer assisted learning leads to enhanced performance through its more visual inputs. The CD ROM brings colour, depth, sound, texture and time-varying motion in a three-dimensional rendering environment. However, the decoding of the various images in a CD ROM demands a certain degree of visual literacy, which cannot be assumed to be present in the two groups. Consequently, a verbal or textual system may be necessary for further elucidation of the viewed content.