Background/Context: Significant research has been done on the cognitive and academic outcomes of older-younger and peer-peer student relationships. Whether in a one-on-one setting or a setting in which responsibility for teaching is shared among members of a collaborative group, well-planned, well-organized, and well-executed student-student interactions have repeatedly shown positive evidence of student progress and learning This action research project differentiates itself from previous research in several ways because it focuses on motivational and attitudinal outcomes when every student in a classroom of eighth graders serves as a teacher of "new-to-everyone" content for three classes of younger students. Purpose/Objective/Research Question/Focus of Study: The research question I asked was: What happens when my eighth-grade students teach younger students about Japan? My purpose was to find out if and how teaching younger students affected eighth graders in my K-8 inner city public school. I was also interested in whether and how the project affected the school community. Setting: The research took place in a K-8 inner city Chicago public school. Population/Participants/Subjects: The participants were 27 eighth-grade students, and a second-grade, a third-grade, and a fourth-grade class of approximately 25 students each. Approximately 96% of participating students were African American, and 4% were Hispanic. Intervention/Program/Practice: The project consisted of a 10-week period during which my eighth-grade class was split into three groups that developed and taught lessons about Japan to classes of younger students. Research Design: This was an action research project that I did in my classroom while teaching full time.