This study has been carried out in order to determine the effect of computer animations in teaching acid and base topics in science and technology courses on the academic success of the primary school students and the opinions of students related to teaching with the animations. This research was conducted by the participation of 55 students from two different classes of 8th grade at a primary school in the city centre of Erzurum during the first semester of the 2006-2007 academic years. One of the classes, in which animation technique was used, was determined as the "animation group" and, the other class, in which the traditional teacher-centered instruction was dominant, as the "control group". Data in this research were collected by Science and Technology Achievement Test (STAT) and Student Opinion Scale (SOS). The data gathered through by STAT were compared by independent sample t test. The results of SOS were presented in table as percentages and arithmetic means. The finding indicates that students taught by computer supported animations were better than those in traditional teaching group. In addition, data gathered through student's opinion scale suggest that students liked computer animations.