As a cognitive-motivational construct, self-efficacy has been researched extensively and has involved two important lines of inquiries, namely the impact of sources of information on self-efficacy and the predictive effect of self-efficacy on learning outcomes. We proposed and tested the relations between the four major sources of information (enactive performance accomplishments, vicarious experiences, verbal persuasion and emotional and physiological states), self-efficacy and academic achievement for mathematics and science within one conceptual model. Our model was tested with the conjunctive use of longitudinal data and latent growth curve modelling (LGM) procedures. Two hundred and fifty-two (110 girls, 142 boys) upper elementary school children from three government schools participated in this longitudinal study. Likert-scale inventories were administered over four occasions within a one-year period. We measured the four sources of information at T[subscript 1], whereas self-efficacy for mathematics and science was measured at T[subscript 2]-T[subscript 4], and academic achievement was measured at T[subscript 4] only. SPSS AMOS v18 was used to test a number of "a priori" multivariate growth curve models. LGM analyses provided moderate evidence in support of our conceptual model, noting different patterns of trajectories for both mathematics and science. (Contains 5 figures and 3 notes.)