Using large, representative samples (N = 76,818) of 15-year-old students in eight countries that took part in the 2018 edition of the Programme for International Student Assessment (PISA) we develop multilevel regression models to estimate the association between boredom and reading and mathematics achievement and multilevel moderation models to estimate the likelihood that students will experience academic boredom as a function of their use of ICT and how enthusiastic they perceive their teachers to be. Students who reported being bored in mathematics classes had lower mathematics and, in some countries, lower reading achievements than students who did not report being bored in mathematics classes. By contrast, results did not reveal a consistent association between boredom in language and literature classes and during self-study and mathematics and reading achievement. The use of ICT for leisure was associated with a higher likelihood that students reported being bored. By contrast, the use of ICT for learning at home was associated with a lower likelihood that students reported being bored. Students who perceived their teachers to be enthusiastic, whether they used ICT or not, were considerably less likely to report being bored. The association between ICT use and boredom was moderated by teacher enthusiasm. In particular, the use of ICT for leisure was associated with higher boredom among students whose teachers lacked enthusiasm whereas the use of ICT at school was associated with higher boredom among students who perceived their teachers to be very enthusiastic.