The complexities of language education demand that teachers have the flexibility to be able to adapt their plans during lessons in order to meet the needs of their students. Yet teachers are trained to meticulously prepare lesson plans and numerous activities to keep their students engaged. This can lead to teachers feeling locked in to the plan they spent time preparing. The Unplanned Lesson suggests a new paradigm for how to prepare for and conduct language lessons based on curating what the authors term "structures." By focusing on structures that are flexible, evolvable, repeatable, and memorable, teachers can reduce the amount of time they spend planning and increase the amount of time students are engaged in deliberate practice. Designed to integrate with any syllabus or textbook, The Unplanned Lesson approach aims to allow teachers to transform their classrooms by giving them more time to focus on supporting their students' learning.