One hundred hyperactive children meeting research diagnostic criteria and 60 community control children were followed prospectively over an 8-year period into adolescence. Younger (12-14 years) and older (15-20 years) groups were tested on measures of academic skills, attention and impulse control, and select frontal lobe functions. At follow-up, hyperactive Ss demonstrated impaired academic achievement, impaired attention and impulse control, and greater off-task, restless, and vocal behavior during an academic task, compared with control Ss. The limited set of frontal lobe measures did not differentiate the groups. Age did not interact with group membership. However, several measures showed age-related declines in both groups. It is concluded that hyperactive children may remain chronically impaired in academic achievement, inattention, and behavioral disinhibition well into their late adolescent years.