In this study, a computerized collaborative concept-mapping approach is proposed. To evaluate the effectiveness of this innovative approach, a learning activity has been conducted on an elementary school natural science course. Two hundred and twenty fifth graders from seven classes were divided into an experimental group, in which the students learned with the proposed approach, and a control group, in which the students learned with conventional computerized concept map approach. From the experimental results, it was found that the students in the experimental group had significantly better learning achievement than those in the control group. Furthermore, the cognitive load of the experimental group students were significantly lower than the ones in the control group, implying that computerized collaborative concept-mapping approach not only reduced the cognitive load, but also improved the learning achievements of the students.