Organized and educational free time that has a goal to teach children some important life skills is a basic mission of every summer camp for children of all ages. The aim of this paper is to examine some characteristics of children that attend summer camp, and which are related with their temperament, resilience and optimism. This survey has 107 participants, 51 of them from a Croatian summer camp and 56 from a Russian summer camp. Cross-cultural comparison of the psychological characteristics of children from these summer camps showed statistically significant difference in temperament, where children from the Russian summer camp expressed higher level of emotionality, activity and sociability. Measurements of the resilience and the optimism didn’t show statistically significant differences between children from Croatian and Russian summer camp. Results of the satisfaction with their stay at the camp reveal statistically significant differences, so children from Russian summer camp expressed bigger satisfaction comparing to children from Croatian summer camp. Examining the correlation of variables, there was a statistically significant positive correlation between the temperament and the satisfaction with stay in camp, and between the resilience and the optimism. At the end, this paper analyzed a problem of preschool camps. The “status” of preschool summer camps is less popular because children aren’t ready to sleepover in the camp. Therefore, there are daily and family camps for which it is important to be filled with fun and development-appropriate activities. In order to achieve this, it’s necessary to have professional animators and successful cooperation with parents. Finally, the paper discusses guidelines for improving the operation of summer camps, also it notices some lacks in their managing and provides recommendations for future surveys.