Cooperative learning involves students working in small groups to help each other learn. It has several benefits: it raises achievement for all students, builds positive relationships, and supports social and emotional development. Effective cooperative groups have five defining characteristics - members strive for a shared goal, hold each other accountable, work face to face, are taught social skills, and reflect on their effectiveness. For cooperation to be successful, lessons must incorporate positive interdependence, individual accountability, promotive interaction, teaching of social skills, and group processing.