Cooperative learning is a teaching method that makes students achieve common goals through joint efforts. This study explores the influence of cooperative learning on learners through a quasi-experimental design, employing a pre-test-post-test data collection method. The Student Team-Achievement Division (Slavin, R. E. 1978. "Using Student Team Learning." Baltimore, MD: Johns Hopkins University, Center for Social Organization of Schools) was used to apply cooperative learning with a one-month intervention. A total of 93 students from two sixth-grade classes participated in the study, who were taught by the same mathematics teacher at a school in Shenzhen, China. This study used a mixed-method approach adopting both qualitative and quantitative methods for data collection and analysis. For quantitative design, questionnaires were used. The data were analysed by SPSS 25.0. Then a descriptive analysis, one-way ANOVA analysis, and ANCOVA analysis were conducted. For qualitative design, data collection included interviews and observation. The qualitative data were transcribed and coded (Edwards, J. A., and M. D. Lampert. 2014. "Talking Data: Transcription and Coding in Discourse Research." New York: Psychology Press), by open, axial, and selected coding.