<![CDATA[This study aimed to examine differences in depression, anxiety, and stress across grade levels among students in a cadet-based boarding senior high school. The study employed a quantitative approach with a comparative design. The participants were 423 students from grades X, XI, and XII, with an equal number of respondents in each grade. Data were collected using the 42-item Depression Anxiety Stress Scales (DASS-42), which measures three psychological dimensions: depression, anxiety, and stress. Data analysis was conducted through descriptive statistics and group comparison tests using ANOVA and Welch tests according to the characteristics of the data, followed by the Games-Howell test for variables showing significant differences. The findings revealed that grade-level differences emerged only for depression: grade XI students reported higher mean depression scores (M = 6.45, SD = 7.73) than grade X students (M = 4.35, SD = 5.62), Welch’s F(2, 275.7) = 3.62, p = .028, with the Games–Howell test confirming a significant grade X–grade XI difference (p = .027); anxiety and stress did not differ significantly across grades. Across all grades, the group mean scores for the three dimensions remained within the normal-to-mild range of the DASS-42 norms. This study concludes that students’ mental health dimensions in a cadet-based boarding school do not develop uniformly across grade levels. Therefore, guidance and counseling services need to strengthen promotive and preventive efforts that are more responsive to students’ developmental phases, particularly in monitoring depressive symptoms among more vulnerable groups]]>
