Cooperative learning refers to the instructional use of small groups in which learners work together to maximize their own and each other's learning. When learners work cooperatively in small groups, they divide labor and share resources among themselves in order to achieve common goals, ensuring that all members learn assigned material. All the assigned material is based on the sheet designed by the cooperative group of teachers. As such, cooperative learning may be one way to raise English learners' self-efficacy. This may also increase learners' academic achievement and increase their awareness of being cooperative as well.This action research investigated the relationship between the efficiency of cooperative learning, self-efficacy, and the academic achievement of senior high school learners of English as a foreign language (EFL). Fifty one students (21 males,30 females), who enrolled in the twelveth grade of a senior high school in Wuxi, participated in the study. The participants involved in various adapted cooperative learning activities based on the designed sheet during two semesters of studying English. Before and after the study, each participant completed questionnaires on learners' perceptions of self-efficacy and cooperative learning. They were also asked to keep diaries and then their responses were correlated with their academic achievement.This action research is based on the theory of cooperative learning, in combination with task-based teaching in high schools. This action research is divided into two stages, of which the first stage mainly carried out the necessary preparation and initial attempt to adopt group cooperative learning in English class. On this stage, the author tried to carry out a variety of cooperative learning and task-based teaching, for example,the students were divided into groups and collected information in different ways for one task, then communicated with team members and drew the conclusion; The second stage focused on the problems appearing on the first stage, and the author made the necessary adjustment and tried to improve the design of cooperative learning tasks.When the analysis of the data revealed that cooperative learning was positively correlated with achievement, learners' perceptions of self-efficacy were also found to be correlated with the efficiency of cooperative learning. Likewise, the analysis indicated that the efficiency of cooperative learning was positively correlated with the perceived degrees of academic and their perceptions of self-efficacy. Lastly, the results were discussed in light of previous research and with reference to the cultural context of the study. |