Despite much research into the development of attention in adolescence, mixed results and between-task differences have precluded clear conclusions regarding the relative early or late maturation of attention abilities. Moreover, although adolescents constantly face the need to pay attention at school, it remains unclear whether laboratory measures of attention can predict their ability to sustain attention focus during lessons. Therefore, here we devised a task that was sensitive to measure both sustained and selective attention and tested whether task measures could predict adolescents’ levels of inattention during lessons. In total, 166 adolescents (aged 12–17 years) and 50 adults performed a sustained selective attention task, searching for letter targets while ignoring salient yet entirely irrelevant distractor faces, under different levels of perceptual load—an established determinant of attention in adults. Inattention levels during a just preceding classroom lesson were measured using a novel self-report classroom distractibility checklist. The results established that sustained attention (measured with response variability) continued to develop throughout adolescence across perceptual load levels. In contrast, there was an earlier maturation of the effect of perceptual load on selective attention; load modulation of distractor interference was larger in the early adolescence period compared with later periods. Both distractor interference and response variability were significant unique predictors of distractibility in the classroom, including when controlling for interest in the lesson and cognitive aptitude. Overall, the results demonstrate divergence of development of sustained and selective attention in adolescence and establish both as significant predictors of attention in the important educational setting of school lessons
