The availability of cheap Wi-Fi internet connections has encouraged schools to adopt Web 2.0
platforms for teaching, with the intention of stimulating students’ academic achievement and
participation in school. Moreover, during the recent explosion of the SARS-CoV-2 crisis that
forced many countries to close schools (as well as offices and factories), the widespread
diffusion of these applications kept school systems going. Despite their widespread use as
teaching tools, the effect of adopting Web 2.0 platforms on students’ performance has never
been rigorously tested. We fill this gap in the literature by analyzing the impact of using
Twitter as a teaching tool on high school students’ literature skills. Based on a large-scale,
randomized controlled trial that involved 70 schools and about 1,500 students, we find that
using Twitter to teach literature has an overall negative effect on students’ average
achievement, reducing standardized test scores by about 25 percent of a standard deviation.
The negative effect is stronger on students who usually perform better
