Perceived life satisfaction during the period of childhood and adolescence can be considered a reliable measure of psychological and emotional growth of children and adolescents. The current study aimed to investigate age differences related to social support provided to students (by teachers, classmates, parents and close friends), and its relationship with school and life satisfaction. The study also examined the significance of social support in explaining students' school and life satisfaction. Data were collected from a sample comprising 390 primary school students in grades 3 - 8 in Croatia. The findings indicate that students perceive a lower level of support received from parents, teachers, classmates and close friends, and lower school and life satisfaction, as they age. Statistically significant differences were found in perceived teacher support and school and life satisfaction between younger and older students. Hierarchical regression analysis showed that age and support from teachers and classmates are significant predictors of school satisfaction. The most significant predictors of students' life satisfaction are support from parents and classmates, and school satisfaction. Finally, the implications of the findings and guidelines for future research are discussed.