This article argues that the most commonly used lesson plan pro formas in language teacher education are inappropriately premised on an outcomes-based approach to teaching, one that is in conflict with what we know about how languages are learnt and how experienced teachers teach. It proposes an alternative, affordance-based approach to lesson planning and makes a number of practical suggestions to modify the pro forma and its role in lesson observation. It is argued that the suggested changes encourage teachers to plan for and respond to the learning opportunities of the lesson, thereby reflecting more closely the practice of experienced language teachers and the reality of differentiated language learning. It also makes recommendations on how such a pro forma could be used in both initial certification and in-service teacher development in a wide range of learning contexts, potentially compatible with product, process, and procedural approaches to syllabus design.