Students are the main body of learning and development. Group cooperative learning is conducive to cultivating students' ability to obtain information through multiple channels and the formation and development of self-awareness. It is a process of mutual teaching and learning and information exchange among students, as well as a process of mutual love, mutual help, emotional communication and psychological communication. Behind this excitement and freedom, it reflects laissez-faire and impetuousness, and reflects some disadvantages of the teaching reform in large classes. Then, how to improve the effectiveness of cooperative learning in mathematics classroom teaching group in the environment of large class size in primary schools? Next, I will organize students to effectively carry out group cooperative learning from the aspects of group building, grasping opportunities, cultivating habits, mutual assistance between teachers and students, and scientific evaluation, so that each student can master knowledge, improve ability and develop thinking in a relaxed and happy atmosphere.

First of all, construct a cooperative learning group with reasonable structure to improve the effectiveness of cooperative learning in large class mathematics classroom teaching group.

In large class teaching, it is difficult to cover all aspects of students' learning management, guidance and inspection because of the large number of students. So all the students can be divided into several study groups according to a certain combination.