Fossil projects can enhance the middle school earth science curriculum.
Fossil projects are a way to teach middle school students about both fossil formation and earth science. Through working on fossil projects, middle school students can learn how rocks are formed, the foundations of evolution and identify animals by the impressions they make in the earth or sand. Middle school project topics include trace fossils, fossil formation and identifying fossils.
Fossilization
Demonstrate the process of fossil formation on the seabed with this activity. Mix around 1 cup of fine sand with 3 cups of plaster of Paris. Separate the mixture into three plastic containers. Color the mixture in one container a shade of dark brown, using dry tempera paint. Color the mixture in the second container a shade of light brown. Leave the third container as it is. Place some shells into the third container. Tell students this represents the ancient seabed. Pour around 1/2 cup of water into the container. Using a sifter, sift a small amount of each of the two brown colors over the shells. This is sediment drifting down to cover the shells. Continue until the shells are covered in a soft "mud" (you may need to add a bit more water). Let the "seabed" dry for a few days.
Digging Out
Use the fossil seabed from the previous activity to demonstrate dig for fossils, or prepare some fossil seabeds in advance. Once the ancient oceans receded, dry land that contained fossils was left behind. Give students small, dull knives or small screwdrivers, magnifiers, small paintbrushes and vinegar and an eyedropper. Students should carefully chisel away the "rock" to reveal the fossils. They can use vinegar to melt some of the rock and the brushes to brush away bits of rock. Students should scrape gently around the edges of the fossils, and not chip or hammer.
Fossil Bag
This makes a good introduction to fossils. Place small fossils into cloth bags -- one fossil per bag. Discuss fossils with the students, and the fact that they are very old. Ask students to describe how they would handle something that was millions of years old. Hand around the bags and ask students to feel the fossil in each bag, but do not open the bag. Students should describe how the fossil feels and what they think it may be. Students could draw a picture of what they think the fossil looks like. Have students open the bags and examine the fossils. Discuss whether they look similar to what students thought.
Make a Fossil
Fossils are formed when an animal dies and the soft parts of its body are gradually replaced with minerals contained in groundwater. These minerals harden as the water evaporates. Students cut a shape from a piece of sponge, such as a bone shape. Make a few small holes in the bottom of a plastic cup and place this on a saucer. Add about one inch of sand to the cup, place the sponge shape on top and add another two inches of sand. Mix 4 tbsp. of bath salts (they must contain magnesium sulphate) with 4 tbsp. of warm water and pour this into the cup. Leave the cup in a warm place. Each day, for five days, add more water and bath salts, as before. Let the cup sit until dry and remove the fossil sponge. The bath salts will have become trapped in the sponge and then hardened, creating a fossil.
Tags: bath salts, fossil formation, Students should, Color mixture, container shade, earth science, Fossil projects
