Adolescent mental health issues are prevalent in Nairobi slums, where access to care is limited. A qualitative study using semi-structured interviews with 30 adolescents from Nairobi slums. Findings suggest that MHSGs provided a supportive environment for discussing mental health issues, though only 50% of participants reported feeling significantly better after attending at least three sessions. MHSGs offer potential support but require further evaluation to enhance their effectiveness and accessibility. Future research should focus on developing culturally tailored MHSG curricula and expanding outreach efforts. Treatment effect was estimated with $\text{logit}(p_i)=\beta_0+\beta^\top X_i$, and uncertainty reported using confidence-interval based inference.