You may wish to consider grouping people during the the initial study to assure a mix of experience levels. In our Book 5 intensive we asked each person to introduce themselves, and include their experience with Book 3. Each name was put each name on an index card along with either a red, blue or green star, but we didn't tell them what the colors signified, and gave them each their card. (Red was for folks with a lot of experience teaching the Book 3 lessons to children, blue for some experience, and green for little or no experience.) When they got into groups we just asked that they have at least one of each color star in each group. Seemed to work well, and eventually they all figured out what the mysterious stars meant.