Ask your students what, if anything, they already know about fossils and write down any information they provide on the board. Explain how fossils are the remains of creatures. Also describe the difference between fossils that come from the actual body of an animal and those made from imprints left behind by both plants and animals. Specify that hard portions of an animal's body, such as bones, teeth and shells, harden because of a process called mineralization, while softer portions, such as flesh, organs and fur, do not. Explain how sediment can fill imprints, like those left by leaves and feathers, and harden to form a rock, creating a lasting impression long after the soft physical remains disappear.
Once your students have a general understanding of what fossils are, give them the opportunity to study fossils in a hands-on manner. Obtain several samples for your students to examine. Fossils made from imprints, rather than those created through mineralization, will be easier to obtain. Either buy fossils from educational supply stores, websites and resellers or find your own samples by combing your local riverbed or beach. Place your students into small groups. Give each student a pair of gloves to wear, and give each group a fossil, a magnifying glass, and a worksheet to fill out for the purpose of describing their fossil.
Briefly describe the work of a paleontologist, explaining that paleontologists study fossils to learn about life that once existed and how the Earth has changed over time. Ask students to speculate what type of information paleontologists might learn and write their ideas on the board. Also ask students to guess what types of tools a paleontologist might use. Describe how paleontologists use masonry hammers, trowels, chisels, brushes and other related tools while uncovering and examining fossils, and emphasize how they must handle what they find very carefully to avoid destroying it.
Place your students into groups. Quickly review how paleontologists use tools to carefully dig for fossils before giving each group a large bucket or other container filled with soil. Each bucket should also contain several sterilized chicken bones or seashells to represent fossils. Give each group a trowel or large spoon to dig up their pretend fossils, a brush to dust the dirt off, a magnifying glass to examine their findings and a worksheet to write their observations and thoughts down. Instruct your students to take turns performing the various tasks so each one has hands-on experience with these major aspects of a paleontological dig.