Abstract: There have been three separate lines of research on children's conceptions of ability as stable: ability as constant across time and situations, ability as capacity, and ability as uncontrollable, and their implications for motivation in academic and social domains. Research has examined the convergences and divergences among the 3 dimensions in elementary school children. However, recent evidence suggests that even preschoolers understand traits (including ability) as constant across situations; they can use past behaviors to predict future behaviors and emotional reactions to future events. In the present study with 4-, 5-, 7-, 10-, 12-year-olds (N=160), we attempted to explore the 3 dimensions of conceptions of ability at a time. The weak correlations, exploratory factor analysis suggested that each dimension represents different understanding of the nature of ability. The conceptions of ability as constant across situations and as capacity reflected developmental differences and conceptions of ability as uncontrollable reflected individual differences in preschool to elementary school years. Moreover, children's conceptions of ability as constant and as capacity developed with different rates. The former were acquired from preschool years and matured in early elementary school years, while the latter did not start to develop until in middle elementary school years and did not reach the mature understanding in late elementary school years, for only half of 12-year-olds understood that ability may increase or limit the effect of effort on performance.

Key words: ability, conception, childre