This article presents a study of academic procrastination and associated motivation variables in 508 adolescents from a general secondary school in central Turkey. Girls reported higher levels of self-efficacy for self-regulation and predicted higher Turkish grades than boys, but there was no difference in levels of procrastination. Academic self-efficacy was a stronger predictor of procrastination for girls than for boys, but for both groups self-efficacy for self-regulation was the strongest predictor of procrastination. Most participants (83%) reported spending one hour or more procrastinating per day, with writing tasks the most prone to procrastination for boys and girls. When procrastinating, Turkish adolescent boys were more likely to spend time with electronic media (watching TV, emailing, going on-line, and, in particular, playing computer games), whereas girls were most likely to read books, magazines, and newspapers. The article concludes with implications for researchers, and also for parents and educators of adolescents. (Contains 5 tables.)