1) Lesson study is a collaborative approach used in teacher professional development where teachers work together to plan, teach, observe, and evaluate "research lessons" with the goal of improving student learning.
2) It is informed by the Japanese concept of "jugyou kenkyuu" and focuses on developing a deeper understanding of how students learn through iterative lesson planning and refinement.
3) Lesson study allows teachers insight into the "pedagogical black box" by collaboratively examining how students engage with lessons, which can help shift practice away from a top-down model of teacher development toward a more dynamic, student-centered approach.