The aim of this study is to examine effects of an instruction on eighth grade students in order to keep desirable balances of their eating and exercising habits. Such habits are quite necessary and important for students to prevent health problems like adult diseases. Balances of diet and exercise play an important role on improvement of students' quality of life (QOL). Additionally, it is important for them to have desirable eating and exercise habits from early childhood. Therefore, I investigated their actual eating and exercise habits which are presumably unbalanced and instructed how to solve issues related to their dietary life in the period of growth by reflecting their own diets. Findings reveal that the instruction was effective enough for students to equip the skills, that is, they fostered attitudes toward their own health and acquired knowledge for self-discipline. With these attitude and knowledge, they acquire the foundation of their well-balanced exercise and eating habits in order to have healthy life in the future.