The document discusses cooperative learning structures in education. It defines cooperative learning as students working in small, heterogeneous groups to achieve a common goal, with each student responsible for their own and their teammates' learning. It then provides details on three types of cooperative learning structures: formal, informal, and group-based. Next, it outlines five key elements of cooperative learning: positive interdependence, individual accountability, equal participation, simultaneous interaction, and group processing. The document concludes by describing several methods used for cooperative learning structures in mathematics teaching, including think-pair-share, sage 'n' scribe/rally coach, and quiz-quiz-trade.