Yellowstone National Park (also part of WY and ID)
A field-trip guide to Yellowstone National Park, Wyoming, Montana, and Idaho: Volcanic, hydrothermal, and glacial activity in the region: USGS Bulletin 2099
Montana Guest Ranch – Group Educations Opportunities
University of Montana SpectrUM – Field Trips with reservations, $3.50 per child.
Exploration Works!: Science Center with group options
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