The objective of this study was to construct a teaching strategy for facilitating students' conceptual understanding of the boiling concept. The study is based on 52 freshman students in the primary science education department. Students' ideas were elicited by a test consisting of nine questions. Conceptual change strategy was designed based on students' alternative conceptions. Conceptual change in students' understanding of boiling was evaluated by administering a pre-, post- and delayed post-test. The test scores were analysed both by qualitative and quantitative methods. Statistical analysis using one-way ANOVA of student test scores pointed to statistically significant differences in the tests and total scores (p less than 0.05). Quantitative analysis of students' responses on each test revealed different schema about changing their knowledge system. Both qualitative and quantitative analyses suggest that the teaching activities facilitated students' conceptual understanding. No statistically significant differences were found between post-test and delayed post-test scores, suggesting that the teaching strategy enabled students to retain their new conceptions in the long-term memory.