Damming rivers has been a case of necessity versus negative environmental impact since the process began. Kids take on the role of a stakeholder in the proposed damming of the Danube River. They begin by reading arguments for and against the project, and then they make a timeline to help synthesize the information. In small groups, they make arguments for or against the project, giving concrete evidence for their assertions. The lesson concludes as the class prepares a three-paragraph response to the original guiding question.