In our mathematics methods courses for elementary preservice teachers, we work to uncover and confront students' understandings as well as misconceptions about important mathematical topics. Karp and colleagues' ("Teaching Children Mathematics", 21(1), 18-25) "13 Rules That Expire" article has been a useful resource for us to highlight and challenge students' mathematical misconceptions. In this article, we share the components of an iteratively developed assignment focused on the 13 rules article. We detail how students explored the "lives" of these rules and investigated alternatives to pervasive mathematics shortcuts and tricks. We posit that our intentionally designed assignment provides an opportunity for students to think critically about their views, beliefs, and misconceptions, which encourages a mindset for preservice teachers to consider the kinds of mathematical misconceptions they will encounter in their classroom teaching. We anticipate that sharing this developed assignment with other mathematics teacher educators could provide opportunities for additional adaptations in unique contexts and continued improvements to support future teachers.