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Dark and Beautiful Caves


Grade level: middle and high school

Caves are formed four main ways: by erosion of rivers, streams, and wind; by flowing lava; by the erosion of sea cliffs by the oceans; and by limestone being dissolved by groundwater. The cavern at Oregon Cave National Monument was formed by underground water dissolving the rock (limestone) along its course. As the limestone dissolved, large holes formed and grew into bigger rooms and passageways.

Water seepage from above the cave drips off the ceilings and walls to deposit beautiful calcium carbonate formations called dripstone. Some of the more common dripstone formations include stalactites, stone icicles hanging from the ceiling; stalagmites, stone icicles growing up from the floor; and columns, formed when stalagmites and stalactites meet. Other formations found at Oregon Caves National Park include draperies, formed when water deposits calcite in thin sheets that hang in delicate folds resembling frozen waterfalls and formed by flowing water; soda straws, hollow stalactites; and popcorn, a knobby mass of rock.

    Students will:
  • Research how caves, and the cave in Oregon Caves National Monument in particular, form.
  • Describe the major stone formations in caves
  • List the stone formations present in Oregon Caves National Monument
  • Make a clay model of the Park's cave that includes the stone formations, and a description of the formations and how they develop.

National Standards:

National Social Studies Standards

Standard 2:
People, Places and Environments:
The study of people, places, and human-environment interactions assists students as they create their spatial views and geographic prospectives of the world beyond their personal locations.

National Geography Standards

Standard 4:
The geographically informed person understands the physical and human characteristics of places.

Standard 7:
The geographically informed person understands the physical processes that shape the patterns of Earth's surface.

National Science Education Standards (Middle School)

Standard D:
Students should develop an understanding of the structure of the earth system and Earth's history

  • a box for each student that is a minimum of 12" x 12" x 12"
  • light brown butcher paper
  • clay
  • Great Lodges of the National Parks: Pacific NW Lodges (PBS video)

    Start with: 330 miles south of Timberline tucked away in southwestern Oregon...
    End with: It's remote location make it the least know of the Pacific NW lodges.

    Start with: At 480 acres, Oregon Caves is among the smallest of national monuments.
    End with: The best know formations in the cave are these composite drapery stalagmite that are also a form of flowstone As if the rock is actually flowing downhill.

  • Toothpicks
  • White paper
  • Scotch tape
  • Scissors
  • Colored pencils
  • School glue
  • Gather all materials other than the video and put them where they'll be available for use during class
  • Ask the class if anyone has ever been in a cave before. If so, ask them to describe the cave to the class. Continue the discussion by asking how caves are formed and what stone formations are present in caves. List their answers on the board. Tell them they will be viewing a video on Oregon Caves National Monument and to use this video to add to the list of their ideas on the board.
  • View video with the class. Explain that they will research caves to understand how they were formed and find what rock formations that can be found inside them. They will then make a cave model using the box, butcher paper, and clay to show the rock formations in Oregon Caves National Monument
  • As they perform the research on the caves, students will keep a list of the rock formations and how they develop. These will then be written or typed as part of the final project.
  • When their research is finished, students will glue the butcher paper inside the box so that it forms an irregular cave wall. They will then mold the clay to make the various rock formations that can be found at Oregon Caves.
  • Each formation will have a little flag stuck into it with the name of the formation. To make the flags, students will cut a small isosceles triangle out of paper and tape the base of the triangle to the top of the toothpick. Color the flags of each formation a different color to make it easier to identify it in the legend.
  • Using the information they researched, students will make a legend for their models. Each formation should be listed with a physical description and an explanation of how that formation forms.
Assessment Suggestions:
    Assessment may be based on:
  • Accuracy of information on the formation of caves and rock formations
  • Quality of the finished cave model
  • Ability to describe rock formations
  • The number of formations included in their cave model
  • Students research where the nearest commercial cave is to them (see web resources below). How did it form and what rock formations are present? Compare and contrast it to Oregon Cave.
  • Take a class field trip to tour a cave.


Coder, K., Taylor, A., Molosky, A., 1990, Caves and Caverns

Kramer, S., 1995, Caves

Sloane, H., Gurnee, R., 1965, Visiting American Caves

Tops, C., 1990, Let's Explore Caves and Caverns

Webber, M., 1998, Awesome Caverns of Marble in Oregon Caves National Monument