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Theodore Roosevelt and John Muir on Glacier Point...

[Detail] Theodore Roosevelt and John Muir on Glacier Point...

Lesson Overview

The debate over damming the Hetch Hetchy Valley in Yosemite National Park marked a crossroads in the American conservation movement. Until this debate, conservationists seemed fairly united in their aims. San Francisco's need for a reliable water supply, along with a new political dynamic at the federal level, created a division between those committed to preserving the wilderness and those more interested in efficient management of its use. While this confrontation happened nearly one hundred years ago, it contains many of the same arguments which are used today whenever preservationists and conservationists mobilize.

This unit includes two separate lessons which set the stage for and explore this particular controversy. While each relates to the other, the two are not dependent on each other and, therefore, may be taught separately. We have sought to provide a framework for instructors along with teaching materials they might print or let their students use online. With the exception of the extension activity suggestions, students will be working with a "limited archive" of our selection.


Students will be able to:

  • identify nineteenth-century leaders and thinkers who influenced the formation of the Conservation Movement;
  • gain an appreciation of the different ways "conservation" can be defined;
  • understand specific differences and similarities between and among those who advocated conservation;
  • understand arguments given to support the conservation of diverse resources;
  • know the major purposes of and provisions of legislation establishing Yosemite as a national park;
  • possess a clear understanding of the controversy that Hetch Hetchy sparked between "preservationists" and "conservationists".


Time Required

  • One to two weeks

Recommended Grade Level

  • 9-12


  • Science, Technology & Business


  • Progressive Era to New Era, 1900-1929
  • Rise of Industrial America, 1876-1900


  • Michael Federspiel and Timothy Hall