Prospectively followed 100 hyperactive children and 60 controls over 8 years into adolescence. At followup, hyperactive children demonstrated impaired academic achievement; impaired attention and impulse control; and greater off-task, restless, and vocal behavior during an academic task compared with controls. Concluded that hyperactive children may remain chronically impaired in academic achievement, inattention, and behavioral disinhibition into late adolescence. (Author/NB)