Compares the adequacy of five theories to predict dropping out of high school before the 10th grade. Theories include full mediation by academic achievement and direct effects related to general deviance; deviant affiliation; family socialization; and structural strains. Results reveal that none of the theories was fully adequate to explain the data, although partial support was obtained for each theory. (Contains 61 references, 4 tables, and an appendix.) (Author/GCP)