The aim of this study is to design and evaluate a peer-training program about changing students' internet use habits. This study was conducted with students from two different elementary schools in Mersin, Turkey, who were enrolled in 7th or 8th grade in the 2009-2010 academic year. A total of 24 students participated in the program, 12 of whom were in the experimental group and the other 12 in the control group. To determine the experimental and control groups, students were given a pre-test. Then, the experimental group was given 10 sessions of 90-minute peer-training program. Immediately after the training, both the control and experimental group were given a post-test, which was followed by observation tests two months later. Besides, in order to observe the effectiveness of peer-training, 387 peer-trainers who took the peer-training program gave two informative sessions of 40 minutes about the secure use of internet in the analysis of the data, Wilcoxon Signed Rank Test and Mann-Whitney U Tests were used.The results suggest that peer-trainers communication skills increased and their peer understanding and peer relations improved. Positive changes in the use of internet have been observed. Students who took training about secure internet use became knowledgeable about secure internet use.