Fan and pick is a Kagan activity which works well to involve all members of a group and to stimulate discussion. Basically, you cut out the question cards and secure them together at one end with a paper fastener so that they can be 'fanned out'. In a group of 4, one person fans, another picks a card and reads it our, the third person answers and the fourth person challenges the response from person number 3. They rotate roles round until all questions have been answered. Alternatively, I have put the areas each question hits along the side so you could allocate questions to students who struggle in that area = easy differentiation!