This is a two-part lesson that demonstrates natural and human impact on an environment by examining changes in a hypothetical river system over time. In part one, students work in groups to solve a problem during one of four different eras; in part two, students present their problems and solutions in chronological order, thus revealing a story of one river over time. Finally, students discuss water pollution issues in their own community and consider possible ways to address those problems.

The Roadmap
Constitutional Rights Foundation
