Materials: Fake Money, three sets of six products, price tags
Divide the group into three smaller groups, consisting of two at a minimum to about 4 or maybe 5 at a maximum. Each group will get their own set of fake money and set of products and price tags, and set up shop. Usually $20 per team is about right, although it would obviously vary if you include more products. The price tags are hidden underneath each item, not according to that item's actual value, so that customers don't know what costs what. Each team takes turns sending out a shopper with some money to the other stores, who tries to guess what's cheapest and buy it. Another person plays the clerk of the store. This is where they can practice both sides of the shopping conversation, including asking the price and so on. After all the stores have sold all their products, some groups will necessarily have more money than they started with, from profits from their store. Other groups will have less than they started with, due to buying expensive goods. Of course, the team with the most money is the winner.