This research aims at studying, by means of a theoretical model, the role of certain personal features (gender, age, socioeconomic background, academic record) and some dynamical mechanisms of personality in predicting the students' achievement in French at junior high school. The dynamical mechanisms, relating to the affective entry characteristics (Bloom, 1979), were represented by five attitudes towards school: Negative feelings, Lack of scholastic interest, Aspirations for future studies, "Scholastic anxiety, worry and stress" and "Nice school, distraction place" (Bennacer, 2003). The academic achievement was estimated by both the teachers' grade in French accorded to students and the cloze test score (relating to French comprehension). With a group of 501 students, the model was tested and affined by the paths analysis. We obtained a final structural model which accounts for the interrela-tionships between variables. It allowed us to identify the profile of the student who gets bad academic results in French. The hereby study shows that personal features (distal variables) have direct effects on academic achievement, or indirectly via the dynamic dimensions of personality (proximal variables). These latter play, in the influence mechanism, a mediating role as dependent and independent variables. This supports the findings of other studies indicating that the affective entry characteristics depend on the personal features and affect the students' behavior and their academic achievement (see Bennacer, 2005; Potvin & Paradis, 2000).