To investigate the contribution of children's beliefs about capacity and strategy to emotions and behaviors in the academic domain, 132 children from two elementary schools in Kyoto, Japan (70 boys and 62 girls aged 10 to 12 years) were given the following assessments: (1) a measure of beliefs about capacity, defined as the extent to which persons believe they have access to certain kinds of potential means (effort, ability, teacher, and luck); (2) a measure of beliefs about strategy, expectations about the extent to which certain potential causes produce outcomes; (3) an assessment of emotional engagement for measuring children's emotions in the classroom; (4) a measure of children's reports of motivated behaviors toward schoolwork, which taps into children's effort, persistence, attention, and participation during learning activities. An analysis of covariance structure was performed to investigate the effect of beliefs about capacity and strategy on emotions and motivated behaviors. The model in this study essentially tested the relationships between scores or measures of beliefs, emotions, behaviors.