The development of mental toughness in student athletes within sports schools is crucial for identifying strengths and improving weaknesses to optimize performance. This study aimed to assess the effectiveness of a mental toughness development program for basketball sports school students. Sixty-two male student athletes, aged 15.83 ± 0.37 years, participated, with 30 in the experimental group and 32 in the control group. They completed the Mental Toughness Questionnaire 48 (MTQ48) before and after the 6-week intervention program. Pearson’s correlations were calculated for study variables. A repeated measures MANOVA followed by one-way ANOVA analyzed differences in mental toughness skills between groups and over time. Results showed a significant effect of the intervention program on mental toughness skills, with small and medium effect sizes. Post-program, the experimental group exhibited higher levels of various skills compared to controls, including skills related to challenge, commitment, emotional control, life control, overall control, self-confidence in interpersonal interactions, self-confidence in one’s abilities, overall self-confidence, and total MTQ48. These findings underscore the utility of interventions for enhancing mental toughness among basketball sports school students, emphasizing the importance of tailored approaches in such intervention programs.