This multi-method, longitudinal study examines the role of teacher attunement (teacher accuracy in identifying the peer group memberships of individual students) in children's peer experiences in early elementary classrooms (1st-3rd grades). Social cognitive mapping (SCM) procedures assessed and compared students' and teachers' reports of peer groups. Peer nominations assessed students' social reputations as popular and as leaders and student-SCM reports assessed students' social network centrality. To account for the nested structure of the data, Hierarchical Generalized Linear Modeling procedures were used. Findings suggested that early elementary grade school teachers tended to have a low attunement to students' peer group memberships. However, when teachers were highly attuned to children's peer group memberships in the fall, results indicated that students were more likely to be perceived as popular and as leaders in the spring and students were more likely to be socially embedded in the classroom social network in the spring. Findings regarding teacher attunement are discussed in reference to teachers' invisible hand and the role of teacher attunement in creating classroom contexts where positive and productive peer relationships are established. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]