Abstract:
The purpose of this study was to investigate the effect of laboratory activities designed based on Prediction - Observation-Explanation (POE) strategy on pre-service science teachers' understanding of acid- bases subject in chemistry III course. A total of 69 pre-service science teachers who took chemistry III course in the fall semester of 2010- 2011 academic year in the department of science education at Pamukkale University participated in the study. Two control groups and an experimental group were employed in the study. Of the participants, 22 pre-service science teachers were in experimental group, 22 pre-service science teachers were in control 1 group and 25 pre-service science teachers were in control 2 group. While approach to laboratory-based on POE strategy was applied to the experimental group and the control 2 group, and laboratory method in the program was employed to the control 1 group over a period of six weeks. A quasi- experimental design and two control groups (C1G, N=22; C2G, N=25) and experimental group (EG, N=22) were used. Acid and Base Concept Test (ABCT) and Science Process Skills Test (SPST) were used for data collection and administered to pre-service science teachers. The ABCT and SPST were administered to the control 1 group and the experimental group as a pre-test and were given all groups as a post-test. Data were analyzed using depended on t-test. The results indicated that approach to laboratory-based on POE strategy provided significantly achievement compared with laboratory method in the program on the understanding of acid-base concepts. Results also indicated that POE strategy helped to gain a better understanding of scientific concepts that are relevant acid- base concepts. As a conclusion the results of the present study showed that activities presented based on POE strategy had a significant effect on pre-service science teachers' conceptual understanding of acid-base. Results showed that POE strategy did not have a significant effect on pre-service science teachers' science process skills subject.
