As the 24 fifth grade ESL students in Alexandria, Virginia, USA settle down after lunch, the teacher asks for attention and announces that the day’s vocabulary lesson will be done in cooperative groups. Several students ask, ‘Which groups, teacher?’ ‘We’ll stay in the same groups of six that you have been in so far this week,’ he replies. ‘I will give each group a different part of a story. There are four parts. Your group’s job is to read the part of a story that I will give you and to discuss the meaning of any new vocabulary words. Use your dictionaries or ask me when you can’t figure out the meaning of a word. In ten minutes, you will form new groups. Three of you will move to another group, and three of you will stay where you are and others will join you. In each new group you will tell your part of the story. You will teach your new group the meanings of any vocabulary words that the group members don’t know. Listen to their part of the story. Learn the meaning of the new vocabulary in it. Then we will change groups again, and you will do the same thing. The third time you will return to your original group and tell the story from beginning to end. You will work together to learn the new vocabulary. After ten minutes of practice time, you will be asked to match each new vocabulary word with its definition on a worksheet that I will give you. Your group will help you during the practice time. During the test you’re each on your own. Your score will depend on your results as a group, since your scores will be added together.’ The teacher then writes the criteria on the board as he explains them: 90–100 percent = No one in your group has to take the test again. 89 percent or less = Everyone in your group takes the test again.