This study was conducted to determine the significance of physical activity in the lifestyles of a selected group of female adolescents. Two groups of girls in their mid-teens, identified through a pilot study, were operationally defined as activity seekers (N=14) and non-activity seekers (N=14). In order to determine the characteristics of both groups and the extent to which movement played a part in their lifestyles, a series of 8 experimental hypotheses were tested over a period of 18 months. Quantitative and ethnographic data were collected by standardized exercise and psychological tests, inventories and questionnaires, teacher surveys, interviews, and school records. Although the two groups scored similarly on some of the variables measured, comparisons found the activity seekers to be significantly different in a variety of ways which are discussed in terms of: physiological functioning; self-perception; health orientation; achievement orientation; perceptual style; cognitive functioning; and personal life style. Results suggest that different teacher strategies in the gymnasium and in the classroom might be required to meet the needs of both activity seekers and non-activity seekers. (LL)