Three teachers create a lesson model focused on modeling and challenge, observing its implementation and discussing positives and issues to adapt the model until agreed upon. They then share the finalized model with the department. Lesson study allows for departmental development around a focus, familiarity with content, student-centered tasks, and consistency within departments, with benefits to students across involved teachers. Potential barriers include time, scheduling, delivery to different groups, and ensuring familiarity with all teaching groups.