As human populations have increased and land uses have changed, many of our rivers have become polluted. This interactive activity models that just as we each contribute to the problem of pollution, we must also be a part of the solution. For this activity, you will read a story about the settlement of the Potomac River (or adapt to your own local river). Each student will be assigned a role in the community and given a prepared canister/container of various types of "pollution." When their par