This experiment uses student participation to teach the concept of diminishing marginal returns. Students are told they will be the employees in a widget factory. This game works equally well in small classes (less than 30 students) and also large lectures (more than 250 students). You will need enough space to place the buckets 16-20 feet apart. If you do not have a large room, you may want to complete the activity in the hallway, outside or in the gym.