Cooperative learning has been proven to be helpful in enhancing the learning performance of students. The goal of a cooperative learning group is to maximize all members' learning, which is accomplished via promoting each other's success, through assisting, sharing, mentoring, explaining, and encouragement. To achieve the goal of cooperative learning, it is very important to organize well-structured cooperative learning groups, in which all group members have the ability to help each other during the learning process. In this article, a concept-based approach is proposed to organize cooperative learning groups, such that, for a given course each concept is precisely understood by at least one of the students in each group. An experiment on a computer science course has been conducted in order to evaluate the efficacy of this new approach. From the experimental results, we conclude that the novel approach is helpful in enhancing student learning efficacy.