Studies on academic achievement worldwide are sporadic, focusing on variables more or less have been taken by the researchers, and provided knowledge. This cross-sectional study aimed to determine how the school effect influences secondary school students' academic achievements by two important significant (study habits and self-esteem). With a covenient sampling method, 400 students from eight secondary schools in Bangladesh were selected for the study. Though the students were equally divided regarding gender (Boys, 200; Girls, 200), they were different regarding school types (Public, 188; Private, 212). Their ages range from 14 to 17, with an average of 14.8. They provided responses on two Bangla version scales: Study Habit Scale and Self-Esteem Scale. Academic achievement was significantly positively correlated with both study habits (r=0.268, p<0.01) and self-esteem (r=0.291, p<0.01). Two predictors of the study were also correlated with each other (r=0.283, p<0.01). Public and private school students were not varied significantly in studying habits and academic achievement, but they were significantly different in self-esteem. The study habits and self-esteem jointly explained 12.3% for public school students' academic achievement while it explained 7.5% variance for the private school students. The discussion implies that how students' study habits and self-esteem facilitate their academic achievement. Further studies will reflect more factors influencing academic achievement.