This study examined how the gradual introduction of home broadband internet across Norwegian municipalities from 2002 to 2007 impacted the academic outcomes of graduates from lower-secondary schools (N = 103,676). Analyses applied sibling fixed-effects models using micro-level registry data on adolescents aged 15 to 16. Findings indicate that broadband internet brought some improvements on students’ performance, concentrated in the subject of ‘Natural Sciences’, followed by ‘Norwegian’ and ‘Arts and Crafts’. Boys’ performance improved with broadband internet about three times as much as girls’ performance. Boys with less-educated parents, with lower academic achievement levels and from Norwegian background benefited particularly from accessing broadband internet. By contrast, girls with less-educated parents worsened their academic performance with new access to broadband internet, while girls of migrant background improved academically. The study reveals how the introduction of broadband internet had heterogenous effects on adolescent academic performance across gender, education, and migrant status in Norway.