The factor structure of functional possibilities of girls is examined 7-8, 8-9, 9-10 years. Indexes are taken into account: physical development, physical preparedness, physical capacity, power level, cardiovascular system, efficiency of adjusting of cardiac activity and indexes of central nervous system. The factor structures of functional possibilities of girls are compared. Comparison exposed the most proof components of individual development. A change the role of different factors is rotined in the process of ontogenesis.