Educational exclusion is a significant issue for pregnant and postpartum adolescent girls in Nigerian informal settlements, where many lack access to formal education due to socio-cultural barriers. A mixed-methods approach combining quantitative assessments with qualitative interviews was employed. Quantitative data were collected through standardised tests and surveys, while qualitative insights were gathered from in-depth interviews and focus groups among participants. Findings indicate that participation in the educational inclusion programmes resulted in a statistically significant increase (p < .05) of 15% in academic performance compared to pre-programme levels. Participants also reported enhanced social support efficacy, with themes emerging around improved self-esteem and increased community engagement. The educational inclusion programmes demonstrated promising outcomes, not only improving academic performance but also enhancing the social support systems crucial for adolescent girls' development. Policy makers should prioritise funding and resource allocation to expand these programmes in Nigerian informal settlements. Schools and local communities need to be engaged as partners in developing sustainable educational models. Educational Inclusion, Adolescent Girls, Informal Settlements, Academic Performance, Social Support