Recent calls for reform in K-16 science, technology, engineering, and mathematics (STEM) education not only emphasize mastery of content, but also call for students to engage in the scientific practice of making evidence-based claims, or scientific argumentation (National Research Council, 2012; NGSS Lead States, 2013). However, students often struggle to separate the process of argumentation from the complexities of the content (Kuhn & Reiser, 2006; Walker & Sampson, 2013). We present an introductory activity that models the process of data analysis and scientific argumentation that uses a simple puzzle based on the characters of Sesame Street. An explanation of the activity, along with preliminary evidence from a pilot study of its effectiveness, is described and is widely applicable to K-16 classrooms as well as preservice and in-service teacher practitioners.