In contrast to the amount of research documenting links between adolescents' individual-level characteristics and their achievement motivation, only a single longitudinal study was identified that identified a relationship between adolescents' peer networks and their achievement motivation. Ryan (2001) examined the relationship between the level of achievement motivation among adolescents' peers and the change in their own levels of achievement motivation from the beginning to the end of seventh grade in an economically and ethnically diverse sample from an urban middle school. The findings of the study suggested that, while intrinsic motivation is generally declining across the seventh grade, adolescents whose peers were more intrinsically motivated at the start of the 7th grade experienced less of a decline in their own intrinsic motivation between the start and the end of the school year than those whose peers were less intrinsically motivated.