Learning about fossils is valuable for students, as it gives them insight into many different subjects: geology, history, biology and evolution. Fossil labs can be both educational and fun, and it is easy to get students interested because they tend to like dinosaurs in the first place. These are some fun, simple labs that teach middle school students about how fossils are formed and what we can learn from them.
Limits of Learning from Fossils
A very simple lab that teaches a valuable lesson about science involves comparing a picture of a skeleton of an animal that the students are familiar with, such as a cat, dog or horse, to that of a dinosaur. Have the students look at the skeleton of the familiar animal and list traits that are known about it, such as fur or skin texture, color, behavioral traits and so on. In a fossil, only hard tissues such as bone or teeth are preserved in the vast majority of instances. Discuss what items on the list of traits would be unknown and which ones could be guessed from the skeletal structure of the animal. Discuss what could be guessed about the dinosaur based on its skeletal structure. This lesson teaches students valuable information about how scientists know what they know about ancient animals and what the limitations are to what they can determine from fossils.
For an activity that gets students moving around, try going outside and looking at sidewalks. Many times, when concrete is poured, a leaf will fall in, or a cat will walk across the concrete or someone will even place their hands or feet into the concrete on purpose. This leaves a record, much like a fossil. Look at the imprint and discuss how old it might be or what might have made it. Look for clues, such as nearby trees.
Letting students make their own plaster "fossil" is a fun activity that also helps to demonstrate how fossils are formed. Press a bone or other item into soft, non-drying clay, then remove it. Spread some petroleum jelly over the imprint and cover with plaster of Paris. Let the plaster harden overnight and peel off the clay the next day. This process, though obviously not done with clay, petroleum jelly and plaster, is very similar to how fossils are formed.
Some of the most interesting fossils are those that are made from the footprints of animals, as these fossils can show us how an animal moved. A fun but messy activity involves painting the feet of some volunteers and letting them walk, run or jump across long sheets of butcher paper in different ways. Let the students look at the patterns that this makes and discuss what kind of movement might have caused each pattern and how they could find out if they were correct in their hypotheses.
- fossil goniatite image by Jim Mills from Fotolia.com