This research was created in order to detect the indirect, direct and total effects of some factors affecting the academic success of secondary school students in Turkish courses. Concordantly, in the research, the explanatory and predictive relationships between students' individual verbal expression self-efficacy perceptions, group verbal expression self-efficacy perceptions, motivation towards school and demographic characteristics (gender, number of siblings, education level of parents) as well as various variables (number of books at home, number of book pages read daily, the daily television watching frequency and daily internet use frequency) and academic success in Turkish lessons were examined. In the study group of the research, there are 506 eighth grade students studying in seven public secondary schools in the city center of Kilis. The data obtained were analyzed with a structural equation model to reveal the indirect and direct causality between internal and external variables through structural equations. As a result of the research, individual verbal expression self-efficacy perceptions and motivation towards school have only indirect effects on students' academic success in Turkish lessons, group verbal expression self-efficacy perception, number of siblings and father's education level have only direct effects. Besides, gender, the number of books at home and the number of daily book pages read have both indirect and direct effects on the academic success of students in Turkish lessons. However, in the study, it was detected that individual verbal expression self-efficacy perceptions, gender, number of books at home, number of daily book pages read, and motivation towards secondary school had indirect and/or direct effects on group verbal expression self-efficacy. [Note: The publication year (2022) shown on the PDF is incorrect. The correct publication year for this article is 2023.]