Cashier - There are four teams of cashiers.   They rotate after each transaction and help one another count back change, read prices, etc.. The must complete the transaction in this order. 
1. Look at price on item.
2. Ask for that amount
3. Take money from customer
4. Hand item and change if necessary.
5. Say thank you

Customer Service - These students will mingle about the room, straighten up inventory as it gets picked through and make sure that all the customers can find what they might be looking for.