Although students are part of a group of classmates, they spend the majority of time during lessons with students who are seated next or close to them. Therefore, near-seated peers in elementary school classrooms might play a crucial role in students academic development. It was hypothesized that near-seated peers influence students academic engagement and achievement, especially when they are also friends. Participants were 559 fourth sixth grade students (21 classrooms; 51.9% boys; Mage = 10.65 years, range = 8-12). Longitudinal social network analysis (RSiena) showed that students academic engagement and achievement got better when friends scored better, and vice versa, regardless of their physical position in the classroom. In contrast, near-seated peers who were not befriended got more diverse scores over time. These results imply that teachers should consider students friendships and academic engagement and achievement in designing seating arrangements. Moreover, it is recommended to actively monitor ongoing peer influence processes.