I just had my phone interview with Kroger last Tuesday. They set me up for an interview on Friday... did they say you're doing a group interview or anything? What they did for mine was they had us answer some questions on a sheet of paper, nothing difficult, then they split us into groups to make a 'product pitch' kind of thing, but all the instructions were there so as long as you have a decent partner it wont be hard. It's like a high school presentation but shorter and without a powerpoint. And after that they asked a few questions that each of us had to answer, just relate to previous experience/give examples and you're fine. (mine was "how do you deal with difficult people" for example)