This study examined grade- and achievement-level differences in 4th-, 7th-, and 10th-grade students' control-related beliefs and relations between students' beliefs and their reading and writing achievement. MANOVA results indicated grade- and achievement-level differences in self-efficacy, causal attribution, and outcome expectancy beliefs but no interaction between grade and achievement level. Canonical correlations identified a single dimension linking students' beliefs to achievement in both reading and writing. Quadratic relations to achievement were found for outcome expectancy and intelligence attributions. As grade increased, beliefs for reading were more highly related to comprehension. skill relative to component skills, whereas beliefs for writing were more highly related to component skills relative to communication skills. At all achievement levels, a similar pattern of beliefs was related to achievement.