Researchers has pointed out that educational game frameworks are still required more investigations to facilitate the harmony of game and learning, as well as its practical use in educational settings. In this paper, we propose a questdriven learning model (1) to address the design issue how to blend learning tasks with game quests. (2) to explore its educational benefits on students' goal setting and continual participation. To this end, a game-based environment, named Quest Island, is implemented based on this quest-driven learning model. In addition, an experiment was also conducted in a primary class to evaluate its effectiveness on three dimensions: goal setting, attempted quest, and accomplished rate. The questionnaire results showed that game quests can contribute to students' goal content and goal intensity. Data of attempted quests also supported game quests' positive influence on goal setting. However, students' academic achievements did not reveal significant differences between the two versions with and without game quests.