All children in Grades 3 through 12 of one school system completed a survey about health habits and beliefs including smoking and eating habits, perceptions of exercise, weight, and parental involvement in health. The surveys were factor-analyzed within grade and sex, and the overall factors that emerged were Smoking Habits, Family Discussion of Health, Family Thinking About Health, Nutritional Habits, and Health Locus of Control. Analysis of variance of each factor revealed that girls generally reported healthier food habits than did boys. However, girls reported more smoking and less exercise. There are also changes in habits and belief with age; junior high school is a particularly important time for the development of several habits. The findings are discussed in relation to theories of child development and the implications for the content and timing of future health education intervention programs with children.