Temporal associations in the relationship between emotional-behavioral difficulty and academic achievement were explored in 2 samples followed from 6th through 8th grade. The first sample comprised 280 students entering an economically disadvantaged urban middle school and the second comprised 318 students entering an affluent suburban middle school. Among disadvantaged youth, emotional indices were concurrently associated with poorer achievement while prospective associations between substance use and achievement were evident. For privileged adolescents, only a significant concurrent relationship emerged between social anxiety and achievement, although nonsignificant trends in the data suggest other, albeit weak, associations. The findings are discussed in terms of similarities and differences in these temporal associations across 2 samples representing extremes of the socioeconomic continuum.