In order to prepare for the exercise you will need to acquire latex gloves (if using real trash). You will also need to have trash bags for the students to look at. Do not use hazardous garbage for this exercise. The best approach is to have coworkers gather non-dirty, non-hazardous trash from their households. The students then can examine the trash and attempt to determine which staff member in your school or office is associated with a given bag of garbage. This exercise encorporates investigative science in that the students are responsible for determining "who owns the trash." They do so by formulating and asking questions of the possible owners. The questions that they ask will be based on what they find in the trash bags. For example, they might find discarded containers for all vegetarian food items. They then can ask around to see if any of the "suspects" is a vegetarian.