In this study, the effects of model based science education on students. ideas about scientific knowledge are examined. The study lasted almost 6 weeks where 7th graders of a primary school in one of the central towns of Izmir metropole participated in with experimental and control groups. While the experimental group received model based science education, the control group received science education in concordant with the textbook of science and technology curriculum. Both groups were given questionnaire of scientific knowledge and five students from each group were interviewed. Finally, it was seen that there is not a significant difference quantitatively between the groups regarding scientific knowledge. However, it was seen that the experimental group improved qualitatively the understanding of scientific knowledge.