In this activity, learners receive a labeled plastic film canister containing a material representing a pollutant (i.e. pencil shavings = a beaver's wood chips). The instructor (or a learner) stands at the front of the room next to a large beaker of clear water and begins to read a story about the history of an imaginary site. As the story comes to the name indicated on a canister, the appropriate learner comes forward, opens the canister, and tells the "audience" what is inside. The contents are then dumped into the beaker of water and the water is stirred. As more and more materials are added, the story periodically asks whether the audience would boat in, swim in, or drink the water. After all materials are added, learners discuss who is responsible for dirtying the water and who is responsible for cleaning it up. This activity is the first of a set of activities on the page and can be used independently or in conjunction with the second activity called "Clean Water: Is It Drinkable?" in which learners design a water filtration system.