Poor school adjustment is a known correlate of peer rejection in childhood. However, the impact of change in sociometric status on children's academic performance over time is unclear. The aim of this study was to determine whether improvement or decline in children's sociometric status would predict corresponding changes in their academic performance trajectories. Two hundred and seventy-two boys and 252 girls in Florence, Italy (mean age at Time 1:7.42 years) and their teachers participated in this 18-month investigation. Hierarchical linear models indicated that children who were rejected by their peers across the four measurement points of the study demonstrated consistently worse academic performance than did children who were not rejected throughout, whereas children who were regularly accepted by their peers performed better in school than did their peers who were rejected one or more times. A number of children who became rejected exhibited an academic decline, but others who became accepted showed improvement. The implications of these results for children, parents, teachers and school administrators are discussed. (Contains 2 tables and 3 figures.)