First Published in 2004. This special issue of Cognition and Instruction features three manuscripts investigating particular aspects of classroom participant structures, specifically in the context of science instruction. Participant structures is a term introduced four decades ago to describe the roles, rights, and responsibilities regarding who can say what, to whom, and when in the course of classroom activity.

First Published in 2004. This special issue of Cognition and Instruction features three manuscripts investigating particular aspects of classroom participant structures, specifically in the context of science instruction. Participant structures is a term introduced four decades ago to describe the roles, rights, and responsibilities regarding who can say what, to whom, and when in the course of classroom activity.