Latent growth models estimated developmental trajectories for adolescents' math and English self-perceptions (perceived talent, success expectancies), values (intrinsic, utility) and task perceptions (task difficulty, effort required). A longitudinal cohort-sequential study included 1,323 participants spanning Grades 7 to 11, with Occasion 1 mean ages 13.19, 12.36, and 14.41, respectively, for Cohorts 1, 2, and 3. Self-perceptions and values declined through adolescence, and ratings about difficulty and effort required increased. Gender differences favored boys for math and girls for English, with little evidence for gender intensification or gender convergence hypotheses. Explanations reference socialization and social-cognitive developmental theories and features of the curricula, with domain-specific patterns implying domain-specific explanations. Existing research is extended by modeling a broadened set of social-cognitive constructs within the Australian context.