NatureBridge, formerly Yosemite Institute and later Yosemite National Institutes, is an American nonprofit organization founded in 1971 that provides environmental education through field studies. It has programs for elementary, middle, and high school students in four national park locations: Yosemite National Park, Golden Gate National Recreation Area, Olympic National Park, and Prince William Forest Park. The organization is estimated to serve 30 000 students each year. Its lessons include hiking, laboratory-style experiments, and excursions in the backcountry.