Equitably expanding technology access among K-12 students has long been viewed as critical for equalizing educational opportunities. But these interventions may influence students' academic outcomes in unexpected ways. Prior research suggests key technological resources, like broadband Internet, are a double-edged sword, conferring both educational benefits and distractions for children. Clarifying the academic effects of technology-oriented investments is particularly important given that the amount of funding devoted to them has spiked over the last five years, owing to the COVID-19 pandemic, when remote learning rendered high-speed Internet access indispensable to instruction. In this study, we leverage Chicago Public Schools' pandemic-era broadband expansion initiative to assess whether overall levels of, and equity in, educational engagement and achievement improved with increased technology access. Analyses reveal a "skill-technology complementarity": broadband program participation boosted remote learning engagement and achievement for previously high-performing students and reduced engagement and achievement for low-performing pupils. We conclude that increased technology access may come with greater costs for low-achieving students and benefits for high-achieving ones--contributing to widening pandemic-era educational inequities. Continued investments in expanding technology access without complementary supports for vulnerable students may further fuel these inequities; counterbalancing the negative effects of technology for low-achieving students is thus imperative.