This paper presents a field experiment examining the effect of drama education on the psychological development of grades 1 and 4 students. The drama curriculum was delivered after school for one day each week for 16 weeks. Students in the experimental group attended drama education classes, whereas students in the control group took part in the other unstructured extra-curricular activities. Pre- and post-tests of creativity, and story-telling test were given to the students. With respect to creativity, the experimental group was found to score significantly higher than the control group. Significant grade differences were also found, with grade 4 students scoring higher on the measure of drawing but lower on divergent thinking than grade 1 students. No sex difference was found. These findings have important implications for the educational curriculum which are discussed. (Contains 2 tables.)