The aim of this study is to investigate the effects of 4MAT Teaching Model and Whole Brain Model on academic achievement in science and to compare those effects with the effect of inquiry based instruction, which suggested by the science course teaching program. This research is designed in static group pre test-post test design. The study group constituted a total of 68 sixth grade students, 29 in Experimental Group I, 21 in Experimental Group II and 18 in the control group. Experimental processes were carried out simultaneously in 3 groups during 32 class hours by one of the researchers. While 4MAT Teaching Model was used In Experimental Group I, Whole Brain Model was applied in Experimental Group II. The control group was engaged in inquiry based instruction. Kolb Learning Style Inventory III was applied to determine the learning styles of the participant students. Academic achievement test was applied as the pre test and the post test. While analyzing the data, the standard deviations and means were calculated and Paired Samples t-Test, One Way Analysis of Covariance (ANCOVA), Wilcoxon Signed Rank Test, Kruskal Wallis Test, and Mann Whitney U Test were conducted. As a result of the research, it was determined that all of the three instructions applied increased the academic achievement in science. Moreover, it was found that 4MAT Teaching Model was more effective than Whole Brain Model in terms of increasing academic achievement. However, it was determined that the effects of 4MAT Teaching Model and Whole Brain Model on the academic achievement in science did not differentiate from the effect of inquiry based instruction. In addition, it was detected that the effects of 4MAT Teaching Model and of Whole Brain Model on academic achievement in science did not differentiate regarding learning styles of the student. On the other hand, it was proved that inquiry based instruction did not support the academic achievement of the students with diverging learning style.