This study examined general features of Lego block creations produced by Japanese adolescents with no known mental health disorders. The block creations of 33 participants were assessed for form, content, and gender differences. Time spent on the task, amount of area covered, and quantity and types of blocks used were measured and correlated with the participants' genders and past experiences with block play. Results showed that males used the dimension of height more frequently than females, and females used plants in their compositions more frequently than males. The number of basic blocks used and the size of the area utilized were greater with participants who had past experiences with block play. This brief report suggests that the projective use of Lego blocks may be an attractive medium in art therapy, especially among adolescents who played with Legos during childhood. (Contains 3 tables and 2 figures.)