This article reports on the development of a Predict-Observe-Explain, POE-based teaching strategy to facilitate conceptual change and its effectiveness on student understanding of condensation. The sample consisted of 52 first-year students in primary science education department. Students' ideas were elicited using a test consisting of five probe questions and semi-structured interviews. A teaching activity composed of three Predict-Discuss-Explain-Observe-Discuss-Explain (PDEODE) tasks was employed, based on students' preconceptions identified with the test. Conceptual change in students' understanding of condensation was evaluated via a pre-, post-, and delayed post-test approach and students' interviews. Test scores were analyzed using both qualitative and quantitative methods. The findings suggested that the strategy helps students to achieve better conceptual understanding for the concept of condensation and enables students to retain these new conceptions in their long-term memory. (Contains 4 tables and 5 figures.)