How many lives does Schrödinger’s cat have?

Abstract Schrödinger’s cat is an iconic example for the problem of the transition from the microscopic quantum world to the macroscopic, classical one. Up to which system size quantum effects can be expected? How can the transition between the classical and the quantum world be characterized? The field of macroscopicity aims at providing answers to those questions, both from a theoretical and an experimental point of view. Here, we present the main concepts in macroscopicity, including macroscopicity measures, experimental realizations and the link to metrology, from a pedagogical perspective. We provide visualizations and intuitive explanations, together with a hands-on activity where students can create their own macroscopic quantum cats from cardboard cells that are in a superposition of being dead and alive.