Here is a more detailed description of the process from Chicago Lesson Study Group:
One of the key components in these collaborative efforts is “the research lesson,” in which, typically, a group of instructors prepares a single lesson, which is then observed in the classroom by the lesson study group and other practitioners, and afterwards analyzed during the group’s debriefing session. Through the research lesson, teachers become more observant and attentive to the process by which lessons unfold in their class, and they gather data from the actual teaching based on the lesson plan that the lesson study group has prepared. The research lesson is followed by the debriefing session, in which teachers review the data together in order to: 1) make sense of educational ideas within their practice; 2) challenge their individual and shared perspectives about teaching and learning; 3) learn to see their practice from the student’s perspective; and 4) enjoy collaborative support among colleagues (Takahashi & Yoshida, 2004).

How to Plan a Lesson Study
The process seems pretty simple, but don’t underestimate the emotional complexities of asking teachers to plan together (and observe one another). As a staff developer, I planned a series of four lesson studies a year. The first one was a disaster. I thought three or four teachers could plan one reading lesson in a single staff meeting. I didn’t realize that the social interactions really slow things down. The topics from which to plan the lesson were too broad and they spent the entire staff meeting discussing that alone.  It took three or four meetings just to plan the lesson. The demonstrating teachers were sometimes very nervous “performing” in front of their peers. As we got used to the process, things improved. The subsequent lesson studies went much more smoothly and teachers often commented that it was their favorite piece of staff development.

In this case, the end result (the lesson demonstration) is not the most important piece. The real valuable work is in the discussions – opening up lines of communication where they didn’t exist before.  Teachers discussing instruction - that’s the goal.

Step 1: Prepare
Create the groups: the only consideration is that all of the members of a group have to eventually teach the same lesson.
Set the framework: use your staff development topics to narrow the lesson possibilities (examples: small group work or a particular reading strategy)
Stress Specificity: When one of the members eventually demonstrates the lesson, the others should be observing the lesson, not the teacher. The only way to ensure that is to minimize spontaneous teaching decisions – the lesson itself has to specify every detail.

Step 2: Plan the Lesson
Give them time: If it’s your first lesson study, allow two or three meetings to plan the lesson.
Use a template: Give copies of a lesson plan template to each member.
Moderate: Be around to ensure the necessary level of specificity. Ask questions like, “On which page will you stop to check for comprehension?” or “How long will you allow the students to discuss?”.

Step 3: Lesson Demonstration
The demonstrator: One teacher will volunteer to demonstrate the lesson. Check in with this teacher often to make sure they feel confident and have the supplies they need.
Hire Subs: You’ll need substitutes for all the teachers involved in the lesson study. You can accomplish the lesson study in a half-day, so you could do two groups in one day (and use each sub for two teachers).
Take Notes: Model for the observing teacher how to take notes about the lesson – not the teacher – and the resulting student behaviors.

Step 4: Discuss
Thank the teacher, but discuss the lesson: When the lesson is over, gather in another place to discuss. The peers will naturally steer the discussion toward complimenting the teacher, “I really liked how you introduced the book”, etc.   The staff developer has to guide the discussion away from the “performance” and toward the lesson itself. Using a discussion protocol helps.
Adjust the Lesson: The observing teachers will now plan to teach the lesson in their own classes. Decide as a group if any changes should be made.
Debrief: Talk about the lesson study process (what went well, what to change).

See other posts for staff developers and administrators