This document discusses managing a paradigm shift from a traditional assessment system to a more formative approach at Casa Thomas Jefferson language school in Brazil. The traditional system involved high-stakes summative exams every 10 weeks that focused on grammar and caused student anxiety. A pilot program implemented more frequent, lower-stakes assessments throughout each module to provide ongoing feedback. While most teachers and students supported the changes, some resisted due to beliefs about how assessment and learning should work. The document emphasizes examining underlying mental models to better manage resistance to change.