Curricula are planned and written by curriculum developers; they serve as instructional guides for educators. Educators make adaptations to written curricula to meet learners' needs and achieve intended learning outcomes. The efficacy of curriculum adaptations is enhanced when educators have a high pedagogical design capacity, which can be improved through effective professional development. Lesson study is a model of situated professional development centered around ongoing improvement of curriculum enactment. Educators work collaboratively to make curriculum modifications and data-driven decisions to improve their teaching practices. Lesson study occurs at regular intervals over an extended duration.