This research aims to explore the effectiveness of using computer-assisted games as a learning media to improve the quality of learning in Chemistry. The research was conducted in Indonesia on high school students in three separate classes or groups, in three separate schools that were randomly selected. There were three stages of data collection -- the pretest at the start of learning, continuous observations during the learning, and the post-test after the learning has completed. The responses obtained were analysed and compared between the control group and experimental groups that use gamification as the learning media. The results of the pre-test and post-test showed that learning activities and learning outcomes in the experimental groups have reached classical completeness. The contribution of this research provided evidence that gamification is an effective medium of instruction for teaching and learning of Chemistry.