Pre- and post-field trip activities
Children are fascinated with these fossils, so it is usually easy to make this geologic topic interesting. Teachers can use this interest to their advantage in engaging the students in a more in-depth, critical thinking activity on how each of the sample fossils was formed.
It should be noted that only a tiny fraction of living things become fossils. Conditions have to be just right to preserve the remains of a plant or animal. Usually, plant or animal remains will be entirely destroyed over time.
Ask the students what forces of nature destroy plant and animal remains? When a leaf falls to the ground what usually happens to it? When an animal dies, what usually happens to it?
These questions lead to learning about the decomposition of matter: Everything disintegrates or breaks down over time. Leaves and plants and skin are eaten by other animals or easily broken down by wind, water, and bacterial decomposition. Even hard bones break down.
However, if the conditions are just right, some leaves, plants, shells, animals, and animal tracks will become fossils. What are fossils? They are remains of plants and animals or animal tracks from our geologic past that were preserved over time.
Usually, preservation starts with rapid burial of the organism by mud, sand, dirt, or ice. Without rapid burial, the organism would easily decay in oxygen-rich air and water.
Petrification and replacement
There are cases where organisms have been preserved not by burial but in amber, hardened sticky tree sap from ancient trees. Petrification and replacement mean that minerals have filled in the small cavities of an organism or have totally replaced the original matter.
Cast or mold
Another type of fossil, a cast or mold, is formed by an organism (usually a shell) being buried by sediments. Over time, the organism dissolves away by underground water, leaving only the hard parts preserved, as in the relatively unchanged mother of pearl ammonite shells.
Carbonization and impressions
This type of fossilization occurs when very fine sediment like mud covers an organism like a leaf. Over time, the liquid and gas components of the plant are squeezed out, leaving behind a thin black layer of the element carbon that made up the plant.
Things to do
• Have the students imagine and write about environments and scenarios of how a sea monster skeleton would have been fossilized or how a leaf came to be fossilized or how fossilized wooly mammoth teeth are found around our area often.
• An example ISAT 2010 science question showed a picture of a rock with shell and water plant fossils in it and asked, "What can you tell about the rock. Was the rock once at the bottom of a sea?"
One of the first things the children will see when they enter the museum is a dinosaur skeleton, Cryolophosaurus, discovered by Augustana geology professor Dr. William Hammer in Antarctica!
• Have the children locate, on a globe or map of the world, Dr. Hammer's airplane flight from Los Angeles, California to Christchurch, New Zealand to Antarctica.
• Dr. Hammer discovered a brand new species of dinosaur which had never been found before so he had to make up a name for the animal! He called it Cryolophosaurus which means frozen, crested, dinosaur. Have the children draw a picture of a new creature that they would like to discover and make up a name for their creation.
• An example ISAT 2010 science question showed pictures of four different dinosaur skulls and asked which dinosaur was probably a carnivore? Teach the children that in general carnivores have sharp teeth and herbivores have flat teeth. Cryolophosaurus has large, long, sharp teeth. What kind of an eater was it?
Natural resources activities
Natural resources are substances that we use from our land, air and water. The object of this activity is to get the students to realize that they use rock and mineral natural resources from the Earth every day of their lives, but may not know it.
It should be emphasized that if a product is not made from grown plant or animal materials, it is mined from our Earth. Few students realize how important geological natural resources are to our comfortable everyday lives.
• Click the link below for great downloadable worksheets from the Mineral Information Institute about natural resources in your classroom! http://www.mii.org/pdfs/classroom
• Mineral and rock natural resources are non-renewable because it takes thousands or millions of years to make more in the earth. An example ISAT 2010 science question asks the student to choose which is a renewable resource: coal, petroleum, gold or wood?