The effects of an instructional strategy on Grade 11 learners understanding of genetics

Abstract

Research into learning genetics has largely focused on issues such as problem solving and the process of meiosis. The central concept of genetics, however, has received very little attention despite the fact that it is one of the concepts that learners find difficult (Ogunniyi, 1999; Bahar, Johnstone and Hansell, 1999; Collins and Stewart, 1989). In view of this, the specific purpose of this study was to investigate: (l) concepts of genetics that grade I I learners hold before and after a period of instruction in genetics (2) the differences in the understanding of genetics held by learners exposed to an instructional model and those not so exposed; and (3) possible influences of gender, age, and language on grade I I leamers' understanding of genetics. The method adopted for this study was a multidimensional approach in which both qualitative and quantitative approaches were used to complement each other. The role of the researcher in this study was that of the participant-as-observer. An induction workshop was conducted for both the combined instructional teacher (i.e. experimental teacher) and the traditional instructional teacher (i.e. control teacher) to help them explore and reflect on their practice with the view to create in them an appreciation for multiple teaching strategies or traditional teaching strategies to teaching and learning respectively. Two schools and two teachers were used in this study. The instruments used in the study were pilot tested in a school with similar characteristics to the two schools used in the main study. The instruments used to generate data for the study include: Classroom Interactions Observation Schedule, Structured Interviews with teachers and learners, Genetics Achievement Test (GAT), a Cloze Test and Learner Worksheet. All the instruments were subjected to the rigour of triangulation to attain a high level of validity, reliability as well as credibility. The findings of this study amongst other things suggest differences in the interactions of behaviours of the experimental teacher and the control

teacher. The control teacher tends to out-talk the learners while the experimental learners tend to out- talk their teacher. Also, the learners in the treatment group (experimental group learners) performed

significantly better than those in the control group. The study was premised on the socio-constructivist epistemology, which construes the learning as knowledge construction based on one's interaction with the leaming environment (Von Glasersfeld 1993; Mintzes dnd Wandersee, 1998). The constructivist epistemology does not assume that the learner enters into the science classroom tabula rasa. Rather, it assumes that the learner holds ideas and views about various phenomena based on prior experience with the environment.