Classified for credit

Large inland aquarium with ocean, freshwater, and rainforest exhibits — covers marine biology, ecosystems, and animal adaptation.

Preserved 1863–1935 Lower East Side tenement with guided tours — primary-source immigration history, urban poverty, and turn-of-century American social conditions.

Commercially operated limestone cavern system — covers speleology, karst geology, cave formation, and mineralogy through guided tours.

World's longest known cave system with guided tours — covers speleology, karst geology, cave ecology, and geologic time.

Mammoth Cave National Park, the world's longest known cave system, offers ranger-led tours covering speleology, geology, and karst hydrology.

Active paleontological dig site where Columbian and woolly mammoth remains are excavated in situ — covers paleontology, Pleistocene geology, and Ice Age ecology.

NPS-managed Civil War battlefield (First and Second Bull Run) with visitor center, ranger programs, and preserved earthworks.

World's first full-scale plutonium production reactor at Hanford Site — covers nuclear physics, WWII history, and the science of the Manhattan Project.

Battleship Cove maritime museum with USS Massachusetts, a destroyer, and submarine — WWII naval history, ship engineering, and 20th-century military technology.

Fleet of historic ships on San Diego Bay — covers naval history, maritime technology, and U.S. military and trade history from the 1500s to WWII.

Major hands-on science center in Baltimore's Inner Harbor — covers physics, astronomy, earth science, and biology through interactive exhibits and an IMAX dome.

Hawaiian marine aquarium with open-ocean tunnel and live reef exhibits — covers Pacific marine biology, coral-reef ecology, and oceanography.

World-class telescope complex atop Mauna Kea — covers astrophysics, optics, atmospheric science, and the geology of shield volcanoes.

World-class observatory summit with visitor center covering astronomy, atmospheric science, and Hawaiian volcanic geology.

Full-scale reproduction of the 1620 Pilgrim ship with costumed interpreters — covers colonial-era navigation, transatlantic exploration, and Pilgrim history.

Working research observatory in the Davis Mountains with public star parties and visitor programs — astronomy, optics, and astrophysics observation.

Major hands-on science center — physics, chemistry, biology exhibits and an IMAX dome.

Large-scale immersive art installation with narrative environments — supports study of contemporary art, storytelling, and interdisciplinary creative design.

UNESCO World Heritage cliff dwellings — covers Ancestral Puebloan archaeology, Southwest Native American history, and cultural geography.

Ancestral Puebloan cliff dwellings at a UNESCO World Heritage Site — covers pre-Columbian archaeology, Native American history, and Colorado Plateau geography.

Best-preserved meteorite impact crater on Earth with visitor center and museum — covers planetary geology, impact physics, and astrogeology.

Observatory at Meteor Crater (Barringer Crater) — impact-crater geology, astronomy, and planetary science.

Visitor center at the best-preserved meteorite impact crater in the world — covers planetary geology, impact physics, asteroid science, and crater formation.

Large accredited zoo with 2,000+ animals and active conservation programs covering zoology, animal behavior, and global biodiversity.