Give students a piece of paper and have them draw their favorite seashells. Compare the different species shared. Place a variety of seashells, bi-valve, uni-valve, and spiral, on the table. Discuss the unique features of each sea creature. Divide students in to groups of two or three. Have each group choose one of the seashells to research. The groups will give the class a presentation that includes visual aids. The report should include the creatures life-cycle, habitat, and other interesting facts.
What do seashells and egg shells have in common? Both are composed of calcium carbonate, a substance also found in chalk, limestone and marble. Calcium carbonate can be dissolved in vinegar. To test sea shells for this substance, collect six similar seashells. Place three of the shells in a bowl and cover them with water. Place the other three shells in a bowl filled with vinegar. Let them set for three days. Rinse them off and lay them on a paper towel to drain. Use a hammer to test for firmness. First, hammer the shells that were not covered with vinegar. Second, hammer the ones soaked in vinegar. Make comparisons between the two types of shells.
Use seashells to learn how to classify information. Give students a bucket of seashells and have them group their shells based on common attributes, such as type of shell, how the animal moved, or where it is found. Set up a display that shows the groupings and explain the reason the shells are placed together. See "The Magnificent Shells of the Smithsonian" video listed in Resources that students could use for a reference when classifying their shells.
Small seashells can be used in assessment for a science unit about the ocean or tide pools. Creating an ocean diorama of the layers of the ocean floor or a tide pool habitat is an effective way to have students demonstrate their understanding of the ocean landscaping and is an alternative to a paper and pencil test. The shells would be used to show an understanding of where such animals live in the ocean. Students demonstrate knowledge by using the correct terms for the sea life.