Science Teachers Designing Theory - Laden Experiments : A Case Study in Human Fertilization

Abstract

This research was a case study, which aimed at investigating 5 science teachers’ ability in designing experiments. The researcher asked two groups of two and three teachers to collectively design experiments to test theoretical hypotheses about human fertilization. The researcher analyzed components of the experiment designed by each group, which included questions, experimental hypotheses, independent variables, dependent variables, and controlled variables. The research results revealed some important limitations the teachers encountered in designing an experiment such as transforming a theoretical hypothesis to an experimental question, identifying and manipulating an independent variable in a continuous manner, giving an operational definition to a dependent variable, and identifying appropriate controlled variables. This research suggests that teacher professional development should focus on facilitating teachers’ understandings about scientific experiments.