We designed a classroom activity to foster students' understanding of what schemas are and how they function. We used a video of the instructor as an infant to illustrate how schemas influence gender stereotyping. Before the video, we told students that the baby was either a boy or a girl. After the video, students rated whether the baby would grow up to possess stereotypically male or female traits. Students in the video condition displayed a greater increase in schema knowledge than a control group that did not watch the video. Students also evaluated the activity favorably. We suggest other possible variations of this activity. (Contains 1 table.)