This computer game was designed and developed to enhance the skills of high school students in balancing chemical equations. The game simulates a trip to the beach and consists of three missions, ranging from easy to difficult levels, enabling players to engage in a contextual learning experience. The objectives of this computer game development were to compare learning achievement before and after using the game and to evaluate the level of satisfaction in learning through the game. The study sample consisted of 27 high school students in Mathayom Suksa four, selected from a medium-sized school in Pathumthani Province, Thailand, using purposive sampling. The research employed two primary assessment tools: 1) a pretest-posttest to assess the understanding of balancing chemical equations and 2) a satisfaction evaluation form to evaluate the computer game. Data analysis was performed using the mean, standard deviation (S.D.), t-test, and normalized gain (<g>). The findings revealed that the mean learning achievement after using the computer game (13.52) was significantly higher than the mean before using the computer game (11.52) at a significance level of 0.01. The overall normalized gain for the class was at a moderate level. Furthermore, the majority of the participants expressed high satisfaction with a mean score of 4.56, indicating that the computer game was user-friendly and conducive to learning. The content, which presented chemical reactions in daily life within the computer game, was also easily comprehensible. Therefore, it could be effectively utilized to enhance classroom learning and applied to other areas of knowledge.