This article examined the factors that influence life-satisfaction and academic grade among primary, junior high, and senior high school students. A total of 3,095 students (961 primary, 898 junior high, and 1,236 senior high students) completed a questionnaire developed by the first two authors and the self-efficacy scale developed by Bandura (1995). Results of analysis of co-variance indicated significant group differences. Specifically, primary school students had higher scores on life-satisfaction, self-efficacy, and social support received from parents. Although the social support received from parents and teachers decreased with age, social support received from friends increased. LISREL analyses indicated that social support influences self-efficacy and life-satisfaction. Secondly, self-efficacy influences life-satisfaction and academic grade. When we examined differences among the providers of social support, the influence of teachers decreases with age and the importance of paternal social support increases with age. Finally, self-efficacy had strong influence on life-satisfaction and academic grades.