The following web sites provide instructions for activities involving plaster casts and molds to demonstrate fossilization. Since many of these activities use plaster, and some use paint or ink, it may be useful to have students where smocks or old shirts on the day you use these activities.
Fossil Preservation Lab , Pamela Gore, Georgia Perimeter College . Provides instruction for making plaster casts from purchased latex molds. Includes worksheets.
Making Fossil Casts, Badlands National Park . Provides instructions for making plaster casts with clay and objects
Moldy Oldies, Utah State Office of Education. Provides short background on different types of fossils and then provides instructions for three activities to illustrate how fossils form. The first models replacement fossils with salt, colored water, and sponges. Film traces uses black paint and a leaf to make a stamp, or impression of the leaf. The third activity involves making casts and molds with different colored clay.
Make Your Own Fossils-Flowers of the Iowa Seas, State Historical Society of Iowa . Scroll down to Activity 3. Provides background, vocabulary, and instructions for making plaster casts of objects in clay. Also, provides instructions for mixing objects in dirt and soil to “make” sedimentary rocks with fossils.
Fossil Hunters , Sand Diego Natural History Museum . Scroll to page 8 for activity. Provides simple instructions for making impressions in clay with plastic dinosaurs and then filling the footprints with plaster to make the molds. Also, has activity in which you coat leaves with ink and make impressions on paper to mimic carbonization. .
Trace Fossils, C. Mankiewicz and C.V. Mendelson, Beloit College . Provides instructions for using student's pets to make trackways and then making casts of the tracks with plaster.