We present the results of an evaluation of the implementation and short-term effects of "Zippy's Friends," a school-based 24-week mental health promotion program to teach children coping skills. The evaluation was conducted in Denmark (322 children in 17 first grade classes) and Lithuania (314 children in 16 kindergartens classes) with control groups in Lithuania (104 in 6 classes) and Denmark (110 in 6 classes). The program was successfully implemented with minimal support. Participants used significantly more positive coping strategies and showed significantly improvement in Social Skills compared to the control groups. In Lithuania, where control group scores on these variables were available, the problem behaviors of Externalizing and Hyperactivity decreased.