Although much evidence suggests that gender stereotyping becomes less flexible during adolescence, results of the present study indicate that gender stereotypes may actually become more flexible at some point during certain adolescent school transitions. The authors measured the flexibility of gender stereotypes in adolescents in Grades 4 through 11, using a combined cross-sectional and longitudinal design. Results indicated that flexibility increased for stereotypes concerning the psychological attributes of men and women after the transition into junior high school, regardless of whether this transition occurred during the 7th or 8th grade. Over the remaining years of junior high and high school, stereotype flexibility decreased. These results help resolve previous inconsistencies found in the literature by suggesting when and why changes in gender stereotype flexibility versus rigidity occur during adolescence.