Seashells are not only homes for sea creatures, they’re also beautiful works of art with their wonderful variety of shapes and colors. Using a rhyming verse, the book Seashells by the Seashore takes readers on a walk at the seashore, counting and naming the shells that wash up on the beach.
LESSON PLAN: Sorting Seashells
This lesson is adapted from one of my favorite resources: Picture-Perfect Science Lessons by Karen Ansberry and Emily Morgan. Students learn about types of seashells as an introduction to scientific classification.
Suggested Grade Level: K-3
- The book Seashells by the Seashore
- Seashell bookmarks available as a pdf download, 2 per student pair
- Assortment of seashells, 6-7 different shells per student pair in a resealable plastic bag
Write the following six statements written on white board or butcher paper: (1) Seashells are made by animals. (2) sea creatures that make shells are called mollusks. (3) Most shells found on the beach can be put into two groups: plants and animals. (4) A bivalve is a shell with two parts. (5) Oysters and scallops are types of fish. (6) When you go to the beach, it’s OK to collect shells with live creatures in them.
- Give pairs of students a plastic bag of assorted shells. Have them make observations about the characteristics of the shells, such as size, shape, texture and structure. Have them use one characteristic to sort the shells into two groups.
- Once the shells are sorted, have pairs switch places with other pairs and guess what characteristic was used to sort their shells. Then have students explain to one another what characteristic they used to sort the shells and why.
- Direct students to the board/chart and read the six questions about shells. Tell students you just want to see what they already know about shells, so for each statement they will indicate whether it is true or false. If they think the answer is “true,” they use their hand to give a “thumbs up” signal; if it’s “false,” they give a “thumbs down” signal.
- Read aloud the book Seashells by the Seashore, including the page that includes general information about shells. During the read aloud, tell students to touch their ear when they hear information related to the statements. Afterwards, read the statements again and have students signal thumbs up or thumbs down. Then write the correct responses: 1-True, 2-True, 3-False, 4-True, 5-False, 6-False.
- Write the words bivalve and univalve on the board. Explain that scientists group mollusks into several classes, the two largest of which are bivalves (such as oysters, scallops, and ark shells ) and univalves (such as whelks, periwinkles, and olive shells). If possible, show an example of a bivalve and an univalve. Point out that bivalves, have a hinge. Place two bivalve shells of the same species together to show how they were once connected by a hinge.
- Pass out two bookmarks to each pair of students and have them identify which shells are bivalves and which are univalves. Conclude by having them check their classification with another pair.
Optional: The lesson from Picture Perfect Science extends the lesson by giving students practice using a dichotomous key for shell identification and also focusing on a hermit crab as an animal that is not a mollusk that uses a shell.
Common Core Connection
- Reading and Literature: Key Ideas and Details (K.3, 1.3, 2.1, 3.1); Integration and Knowledge of Ideas (K.7, 1.7, 2.7, 3.7)
- Science Framework Connection
LS1-A: Structure and Function
- LS1-B: Growth and Development of Organisms
- LS2-A: Interdependent Relationships in Ecosystems
- LS3-A: Inheritance of Traits