With the present study, we aimed to evaluate the effectiveness of youth development program implemented in one of the high schools in Vilnius, Lithuania. 351 ninth to tenth grade students participated in an 8 weeks long Youth Development (YD) program with the 4 month long optional volunteering possibilities and were compared to 262 students in a demographically and academically similar control high school. Both the participants of the YD program and the controls were evaluated three times during one academic year. Pre-test, post-test and follow-up evaluations in an experimental and control group were conducted. The results showed limited time effect on connection. The change of contribution, internalizing and externalizing problems to the direction opposite than hypothesized were found over the one year for both groups.