The relative influence of adolescents closest friends and their friendship group on their cigarette smoking and alcohol use was investigated in a short-term, longitudinal study of 1,028 students in the 6th, 8th, and 10th grades in 2 school systems. The amount of influence over the school year was modest in magnitude and came from the closest friend for initiation of cigarette and alcohol use. Only the friendship group use predicted transition into current cigarette use, whereas only the close friend use predicted transition into current alcohol use. Both group and close friends independently contributed to the prediction of adolescents' drinking to intoxication. No difference in the amount of influence, was found between stable and unstable close friendships or friendship groups; neither grade nor gender of the adolescents related to the amount of influence.

No abstract

Structural aspects of school-based peer networks of adolescents in 6th to 12th grade were mapped in 3 school systems. Female students were more connected to the peer network than were male students, and peer networks became more exclusive with increasing grade. The results also suggest that numeric minorities usually are less connected to school peer networks than the majority group. There was mixed evidence for hierarchical organization of the peer network. Best friends were highly embedded in friendship groups, but neither friendship group nor best friendship was highly embedded in social crowd. Adolescents name friends who are not in their friendship group and usually do not name everyone in the friendship group as a friend.

A randomized experiment of Comer's School Development Program was conducted in 23 middle schools in Prince George's County, Maryland. The school population is predominantly African American, with considerable internal variation in household socioeconomic standing. This study involved repeated measurement with more than 12,000 students and 2,000 staff a survey of more than 1,000parents, and extensive access to student records. It showed that Comer schools implemented some of the program's central elements better than control schools, but not all or even most of them. This shortfall in program implementation may have been responsible for students in the experimental schools not changing any more than controls. Quasiexperimental analyses showed that the program theory may be correct in many of its predictions about student changes in psychological and social outcomes, but not achievement. However, achievement gains were found in schools with a more explicit academic focus, suggesting that improving this focus should be as central to Comer's program theory as improving a school's social climate. Even more needed, though, are ways to improve program implementabtlity, the sine qua non for student change.

We examined friendship selection and termination on a wide variety of variables using longitudinal data from 1183, 6th, 8th and 10th graders in two school systems. To control for the effects of peer influence on similarity, adolescents were matched at Time 1 with the persons they would become friends with by Time 2. Adolescents were significantly similar to Time 1 about-to-be friends on minor delinquency and cigarette and alcohol use, the number of reciprocated friendships and activities suggesting that friendship selection was based on these variables. The similarity seen on covert variables such as values and personality could be accounted for by selection on problem behaviors. Adolescents were as similar to stable friends as to about-to-be friends, suggesting that selection plays a stronger role in similarity than influence. Termination was related to fewer variables than was selection.