Help finding a book (title)

[zone97]

I read a book back in highschool, this book was about some kids (young adults) who were taken/captured and placed into a room, this room had a stair case that went up and down to nowhere, in the middle was a landing that had a single sourse of water and a thing that dispenced a food item.. At first it was doing this regularly, then as time goes on the people had to do things to get to release food, like slap each other and other behavioral things. at one point when a light came on they had to all dance for food to show. At the end of the book, they were released, and saw a traffic light come on and they all started to dance...

Its and ODD book, but would like to read it again.. Anyone recognize this?