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Science Projects With Eggshells

Science projects often require expensive materials that may only be available in chemistry shops or specialty stores. An eggshell project can be performed with little cost, using some basic items found in most households. A project that limits the materials to basic, commonly used items can help children become motivated and interested in science.

Eggshell Geode Crystals
- Eggshell geode crystals demonstrates how natural geodes form on rocks. The eggshells hold a water solution; therefore, crack eggs close to the narrow end. Clean and remove the egg membrane -- its lining -- from the eggshells. Add 1/2 cup of a soluble solid, such as table salt, sugar, baking soda or cream of tartar to a cup of boiling water. Stir the mixture until the solid is thoroughly dissolved. Continue stirring while adding small amounts of the solid until the water will no longer dissolve the solid. Add a few drops of food coloring to the mixture. Stand the eggshells in an egg carton lined with waxed paper and then pour as much of the mixture as possible in each eggshell. Place the eggshells in a safe place where they will not be disturbed while the water evaporates. As the water evaporates, the soluble solid initially dissolved in the hot water becomes solid again and forms crystals inside the eggshells. The crystals form in the same way natural geodes form when mineralized water seeps into air pockets in rocks.
Eggshell Strength
- This project demonstrates the strength of an eggshell. Wind a piece of masking tape around the middle of two eggs. Make a small hole in each egg with a sharp point, such as fingernail scissors, and then pour out the contents of the eggs. Cut the eggs equally in half and then position the eggs, upside down and close together, to form a square-shape on a table. Lay a square-shaped piece of heavy cardboard on top of the eggs then place books on top. See how many books the eggshells can hold before breaking. The strength of an arch is proven in this experiment.
Naked Eggs
- Place a few eggs in a container large enough so they are not touching each other. Add enough vinegar to cover the eggs. Cover the container and refrigerate for 24 hours. Carefully scoop out the eggs, replace the vinegar and refrigerate for another 24 hours. Remove the eggs and notice that the shell has disappeared. The acetic acid (vinegar) caused the eggshell, consisting of calcium carbonate, to dissolve.
Smell Test
- Perform this basic experiment to learn if an eggshell is effective at preventing smells from entering inside the egg. Place a hard-boiled egg into a container with a crushed garlic clove. Close the lid, and refrigerate overnight. Remove the eggshell and then smell the egg.

Rocks & Minerals