This paper offers insights on how to facilitate student-student interaction in the science classroom. These insights derive from the education and the linguistics literature. Cooperative learning research offers a means of understanding what helps groups of students interact successfully. Systemic functional linguistics provides tools for analyzing how people use language to achieve various aims. In this article, cooperative learning and systemic functional linguistics are first described. Next, they are used to analyze a transcript of student-student interaction from an elementary school science classroom. Then implications are suggested as to how these two areas of inquiry can inform improved teaching practice. Particular emphasis is placed on the teaching of collaborative skills. Interaction plays a crucial role in learning, and even at an early age interaction is crucial. Successful interaction depends a good deal on skill on the part of the interactants. With specific reference to learning at school, constructivist and Vygotskian views both stress the value of student-student interaction. Ideas are illustrated and disseminated for enhancing interaction. The paper is divided into three sections: the first presents a brief introduction to cooperative learning (CL) and systematic functional (S/F) linguistics; the second focuses on using early CL and S/F linguistics to analyze a small bit of interaction of 3 primary school students; and the final section suggests how insights from CL and S/F can in tandem inform pedagogy. (Contains 56 references and 2 appendices.) (KFT)