The purpose of this study was to test the influences of prepared instructional material based on the 5E instructional model combined with CCT, CC, animations, worksheets and POE on conceptual changes about floating and sinking concepts. The experimental group was taught with teaching material based on the 5E instructional model enriched with different teaching methods and techniques including: POE, worksheets, conceptual change text, concept cartoons and animation activities. And the control group was taught with teaching materials based on the 5E instructional model conducted by the Ministry of Education. The pretest, posttest and delayed posttest were applied to the experimental and control groups. Obtained data was analyzed qualitatively and quantitatively. It was seen that students in the experimental group provided more correct reasoning than did the control group in posttest and delayed posttest. Most of the students in the control group have not changed their alternative concepts in the posttest, although the experimental group students moved their alternative concepts in the posttest. (Contains 5 figures, 10 tables and 3 graphs.)