The purpose of this study is to examine the relationship between a child's self -expectation regarding his academic performance and the following variables: academic achievement, subject preference, persistence, and willingness to challenge in a school task. In study 1, a two dimentional (level and confidence of the accuracy) measure of expectation was constructed and validated on 266 fifth and sixth graders. The psychometric properties of the new scale were presented. Level of expectation and confidence for expectancy level were manipulated in study 2, and their impact was assessed by several achievement behaviors. The confidence for expectancy level was found to influence all achievement behaviors, whereas the level of expectation did not significantly affect any achievement behaviors. Thus, the importance of studying confidence for expectancy level as a predictor of academic attainment was suggested. Implications of further extention of expectancy theory to educational behavior were discussed.