This is a great cooperative learning activity!! Students work in groups of three or four. Question cards are stacked in the center of the table. Students take turns being the showdown captain. The captain picks up a task card and reads the problem to the students. All group members work on the problem using their white board. Once everyone is finished the captain says "Showdown". Group members share their answers. If correct, the team celebrates; if not, teammates reteach then celebrate. The person on the left of the Showdown Captain becomes the new leader.