Two studies of how elementary school and middle school-aged children's general self-esteem, competence beliefs, and subjective taskvaluesfordifferent activities change overtime are presented. In Study 1, elementaryschool children completed questionnaires once a year for 3 years. Study 2 assessed how the transition to junior high school influenced children's self-beliefs. Children completed questionnaires in the fall and spring of their sixth-grade year in elementary school and the fall and spring of their seventh-grade year in junior high school. Results showed that children's self-esteem did not change during elementary school but decreasedfollowing the junior high transition. Children's competence beliefs and beliefs about the usefulness and importance of different activities generally decreased. Children 's interest in the activities showed a more mixed pattern of change. Boys' and girls' beliefs and values differed in fairly genderstereotypic ways.