We investigate the impacts of school-based internet access on second graders’ test scores,
using over 2 million student observations from a panel of Peruvian public primary schools. We
identify effects up to 6+ years after installation on different cohorts of second-grade students,
exploiting variation in the timing of internet access induced by the rollout of a national program.
We find positive but modest short-run impacts, but importantly, these effects grow for subsequent
cohorts. Indeed, short-run estimates alone would have led to different conclusions. These
dynamics underscore the value of extended evaluation windows to allow benefits of educational
technology to materialize.