Applied online and then received an e-mail contacting me to set up a group interview time. Going to one, I did an interview along with 7 other people and two coordinators.
We each took turns introducing ourselves. Then we were each given a merchandise item (swimsuit, towel, water toy, etcetera) and asked how we would try to sell it to a customer by describing its use and how it could benefit them. We had a teamwork project where we then tried to make a structure out of toothpicks and marshmallows. Then they asked a couple more customer service questions. Finally we were all put at a table and read off a paper packet, reciting scenarios like we were talking to a customer, or singing the park Happy Birthday song (though we all talked at the same time so it was chaotic and I'm not sure how well the could judge us). Last part of that was that they tested our accuracy in cashiering with play money and then we could leave, and they would contact us afterwards about results.
Group interview probably took maybe an hour at best.