Elementary Education pre-service teachers are noted for disliking and even fearing mathematics, so a teaching strategy that increases their enjoyment of mathematics learning must be a powerful one, indeed. When the same strategy can also support problem posing and assess mathematical knowledge and reasoning, providing an occasional alternative to testing, it becomes something to share with other teachers. In this article, we share our experiences with having students represent their understanding of mathematical concepts through cartooning in a Mathematics Education course for Early Childhood Education pre-service teachers. We believe these strategies will work with much younger students, and we suggest future avenues for refining the technique. Data for this study include the cartoons students produced and their answers to a survey on the process of using cartoons to represent their mathematical understanding.