This article reports on the relationship between the educational performance of second-generation students, the attitude of majority society towards immigrants and integration policy in the destination country. It argues that the educational underperformance of second-generation students is to some extent a product of an inequality in different students' abilities to materialise educational opportunities provided by the destination country's education system. This inequality in abilities is generated by the human diversity of the different groups: immigrants vs. non-immigrants; voluntary immigrants vs. refugees. Depending on the integration context, the human diversity may exacerbate the inequality and cause the performance gap to get wider. The article uses data from two qualitative studies with the Somali community in Finland and employs the capability approach. Due to their background as the children of refugees from Somalia and the attitude of people in mainstream society, Finnish-Somali students face more challenges in materialising educational opportunities. The Finnish context in which they find themselves puts these students in a less encouraging position for two reasons. First, prejudice and discrimination may weaken their will and confidence to learn and reduces their parents' will to cooperate with their schools. Second, their parents-due to their lack of knowledge of the school system and proficiency in the Finnish language-are also relatively less effective in the Finnish schooling system. To deal with the performance gap between immigrant and native children in schooling, public policy should focus on how the integration context is shaping diverse students' abilities (capability sets) to succeed.