SWELL SHELLS
Grades K - 2

This lesson will help students to discover that the seashells found along sandy shores are formed by animals and that these shells help to protect the small animal inside. Students will also observe similarities and differences in shells and classify them in various ways.

Reading Rainbow #903: Seashore Surprises

Students will be able to:

• Recognize that the seashore contains many living organisms.
• Understand that shells are formed by animals and are actually the remains of animals that once lived in the ocean.
• Explain that the animals live inside for protection from predators, the wind, the sun and the power of the sea
• Determine properties that can be used to classify shells (color, texture, design (striped, spotted, etc.), size, shape)
• Classify shells as univalves and bivalves.

For the student:

• 1 zipper-style bag of 5 assorted shells (for previewing activity)

For the class:

• Rhyme printed on chart
• blank chart paper
• board, chalk
• pictures of various shells
• whelk egg case (if available)
• If possible, have at least one or two shells with the animal still inside (these can be obtained from a member of a local Shell Club -- they freeze them with the animal inside)

• mollusk
• shell
• univalve
• bivalve
• seashore

Teacher: "How many of you have ever been to the seashore? (If you are in a part of the country where the answer may be "no", you can also ask, "Has anybody seen a picture of the seashore?") What did you do there? What did you see there? Where is the seashore and how did you get there?" Look at a map or a globe to help them understand. Teacher: "Let's list on this chart things we have seen on our trips to the seashore." Teacher will write the words on the chart as the students respond.

After the word "shell" is mentioned by a student, the teacher should ask, "Where do shells come from?" Accept all student responses. Introduce the rhyme, "Five Little Seashells".

Distribute individual bags containing 5 shells to each student and have the students place the five shells in front of them and participate by taking away one seashell at a time as the poem ("Five Little Seashells") is recited.

FIVE LITTLE SEASHELLS

Five little seashells lying on the shore,
Swish! went the waves, and then there were four.
Four little seashells cozy as could be!
Swish! went the waves, and then there were three.
Three little seashells all pearly new;
Swish! went the waves, and then there were two.
Two little seashells sleeping in the sun;
Swish! went the waves, and then there was one.
One little seashell left all alone
Whispered "Shhhhh" as I took it home.

Using Math Extension Activity #5
(found at the end of this Lesson), repeat the activity while turning it into a math activity.

Teacher: "Now let's look at our five shells and think about how these shells are alike and different. Who can tell us one way in which they are alike?" (Continue on to discuss how they are different. Tell the students to put their five shells into two groups. For example, one student might group the shells into those that are light in color and dark in color. Another student might group them by rough and smooth or large and small, etc. Hopefully, at least one student will group them by univalves and bivalves, but don't introduce those terms yet).

Teacher: "Today we are going to watch a part of a video about the seashore. I want you to watch and listen for the part that tells how shells are made."

BEGIN video at the scene where LeVar talks about waves being like 24-hour delivery service bringing things to and from the shore.

PAUSE video when LeVar says "they lived their whole lives inside." Teacher: "Why did the animals make these shells?" (They should state that they made them for homes and for protection. Discuss that it's like having a skeleton on the outside. The shell serves as a skeleton for the animal inside).

Teacher: "What do you think animals that live inside shells look like?" (Accept responses that say they are similar to snails since that will probably be the prior knowledge of most of the students. Other students may have had the experience of seeing live animals inside a shell). "How do you think these animals protect themselves? Let's watch the next part to find out."

RESUME video where LeVar says, "These shells are empty. The animals are long gone."

PAUSE video where LeVar states that "Shells are fascinating to look at whether there's an animal inside or not."

Teacher: "What did the banded tulip look like?" (Accept dark, soft, purple, muscle-like). "How did it protect itself?" (Discuss the trap door and, if possible, have a banded tulip or other similar shell with the animal inside for the students to see first-hand).

"How do you think other sea shell animals could protect themselves?"

Teacher: "Now we're going to see many different types of shells. Notice how they look and how they are alike and different. See how many you can remember. At the end of the segment, I want you to notice how the coquinas protect themselves from the birds."

RESUME video.

PAUSE video where LeVar says, "Bye, bye coquinas, bye, bye."

Teacher: "How did the coquinas protect themselves?" (Elicit response that they burrow in the sand to get away from the birds.

Discuss the difference between the banded tulip and the coquina in appearance and in how they protect themselves. (The banded tulip closes a trap door over itself for protection and the coquina stretches out a foot between the two parts of its shell and buries itself in the sand).

"Let's list the different types of shells seen so far today in this segment (jingle shell, spiny oyster, pen shell, kitten's paws, coquinas, olive shell)." (After making the list, hold up a picture of each shell next to the name on the board or on a chart). "In the last segment you will see a very unique shell called a lightning whelk. I want you to watch how this shell reproduces or makes more lightning whelks."

RESUME video.

STOP video where LeVar says "It's incredible that in six years these babies could grow to be giants like this."

Teacher: "Where does the lightning whelk mother store her babies?" (Discuss that the mother lays several eggs in a small, flat egg case which she has made. Each case resembles a nickel. Before she is finished, the female will have made a number of cases, each containing several eggs. The cases are all fastened together by a string or cord that the mother has also formed. The first case is attached to a rock in shallow water. The string of cases float in the water and serve as a home in which the baby whelks will begin to grow. When the baby whelk leaves the pouch it must begin to look for food. If possible have an egg case for the children to see.)

"Let's add the picture of the lightning whelk to our chart."

Teacher: "We have just learned a lot about shells; how they are formed, the animals inside, how they protect themselves and how they are alike and different. Let's look at the shells we saw in this program and see how we might classify them into two groups." (Accept all responses, but when a student responds that some shells had one part and others had two parts say, "Yes, this is how scientists might classify shells.")

Hold up a shell with one part and say that it is called a univalve. Write univalve on the board and discuss that "uni" means one. "Can you think of any other words that begin with uni?" (unicycle, unicorn)

Hold up a shell with two parts and say that a shell with two parts is called a bivalve. Write bivalve on the board and discuss that "bi" means two. "Can you think of any other words that begin with bi? (bicycle, bifocals, bi-level)

"Let's group the shells on our chart into those that are univalves and those that are bivalves. Remember that univalves have one part and bivalves have two parts."

Teacher: "Now you will get the chance to group the shells in your bag into those that are univalves and those that are bivalves." (Review one additional time the definitions of univalve and bivalve. Allow time for the students to do this activity and circulate around the room to assist as needed).

Invite members of a local shell club to visit your class or become pen pals with a class living near a seashore. If you live near the seashore, plan a class trip there to collect materials to add to a seashore collection.

Computer Integration:
If your school has IBM Eduquest Courseware have students work in the Nature of Science series "At the Seashore." This program uses video, photographs, animation and recorded sounds to take the students on a field trip to the seashore. Through the use of this program, the excitement of the seashore is brought right into the classroom. Allow the students to explore to find living things along the seashore. Using the "Seashore Visit" program, take the students on a tour including the beach, the shallow waters right off the beach and a coral reef. Using the "Seashore Guide" program students have access to a database of information about many sea animals. In this program, students create scrapbooks and write about sea animals in the NatureWriter.

Math:

• SHELL SHOP - Students will sort sea shells into various groups. Each student or small group of students will select ten shells and sort them by similarities and differences. Students may wish to bring sea shells from their own collections. As a follow-up to this activity, use the worksheets labeled "univalves" and "bivalves" along with the page of 15 shell cards. Students will color, cut and paste the shells in the appropriate spaces.
  
  
• SEA SHELL ESTIMATION - Depending upon the time of year and the grade level, place a number of shells inside a clear plastic jar or container. The earlier in the year and the younger the students, the smaller the number of shells you will use. The students will estimate the number of shells in the jar and will write their estimates on a shell-shaped chart. When all students have had a chance to estimate, the teacher will pour the shells out on the overhead and assist the students in counting them.
  
  
• SEA SHELL TIC-TAC-TOE - Make a tic-tac-toe board from cardboard (approximately 2' X 2'). Use colored tape to mark off the squares into 8" X 8". Spray paint 5 univalve shells red and 5 bivalve shells gold (or any other two colors). Two students can play this game. You may wish to make more than one.
  
  
• SEA SHELL PROBLEM SOLVING - Student will use the grid to solve the problems. See the attached sheets labeled "Seashell Show" and "Seashell Search."
  
  
• FIVE LITTLE SEASHELLS - Have the children recite again the rhyme from the beginning of the lesson. This time have the children write the number sentence each time the waves take away one shell. You may wish to have individual students come to the board to write the number sentences (5-4=1, 4-1=3, etc.)

Science:

• Have a center set up for exploring a seashore collection brought in by the students and teacher. Include hand lenses, a microscope, a collection of shell books, collectors' guides, etc.
  
  
• Mystery Box - Play this game to help young children identify shells. Use a box that once contained wine bottles. They will usually have nine openings. Cut a circular hole in the bottom of each of the nine openings. Lay the box on its side and place a different shell in each space. Students will reach in without looking and try to guess the shell. It is helpful (especially to younger children) to have two of each shell. One is placed in the box and one on the table to help them match.

Language Arts:

For creative writing, have each student hold a large lightning whelk up to his ear. What do you hear? Write about it. Use this poem as an introduction to this activity: I found a great big shell one day Upon the ocean floor. I held it close up to my ear, I heard the ocean roar! I found a tiny shell one day, Upon the ocean sand. The waves had worn it nice and smooth, It felt nice in my hand.

Create a class big book "Seashore Dictionary." Each student will choose one seashore word (shell, crab, bivalve, univalve, mollusk, etc.) and define it with illustrations and sentences if able. The pages will be organized alphabetically and placed in a binder to keep them all together.

Art:

• Fish Bowl Collage -
  Materials:
  • tagboard equal parts of liquid starch and white glue mixed with a small amount of blue tempera
  • margarine tubs
  • brushes

Collage Materials:

• construction paper scrapes
• nylon net from onion bags
• small sea shells
• green tissue paper scraps
• colored aquarium gravel

a. Cut a fish bowl or aquarium shape from tagboard.
b. Paint entire surface with glue mixture.
c. Before glue dries, create an underwater scene with collage
materials.

• A Bit of the Beach -
  Materials:
  • paper bowl
  • plaster of Paris (about one cup per student)
  • beach sand (about 1/3 cup per student, plus a little extra.)
  • water
  • spoon or craft stick
  • tiny seashells, twigs, other nature objects
  • small fabric scrap
  • miniature paper umbrella (optional)

a. Put the plaster and the sand in a bowl, add water and stir with a stick or spoon until well-mixed.
b. Create a beach scene on top of the plaster by sprinkling with extra sand.
c. Add tiny shells, nature objects, "beach towel" fabric scrap and umbrella. Let dry.
d. Remove beach scene from bowl and use as a paperweight.

Miscellaneous:

• Beach cups - (very similar to "dirt cake"). Makes about 10 servings.
  Ingredients:
  • 35 vanilla wafers
  • 2 cups cold milk
  • 1 pkg. (4 serving size) vanilla instant pudding
  • 1 1/2 cups whipped topping
  
  Decorations:
  • a plastic beach pail
  • gummy sea shells, worms and sharks
  • candy stars, chopped peanuts, gumballs
  • miniature umbrella

Crush vanilla wafers in a zipper-style bag with a rolling pin. Pour milk into pail. Add pudding mix. Beat with a wire whisk until well-blended (about 1-2 minutes). Let stand 5 minutes or until thickened.
Stir in whipped topping. Gradually add one cup of crushed wafers. Top with remaining crushed wafers for beach sand. Refrigerate until ready to serve. Decorate just before serving.

• Create a "beachy" reading corner by placing a couple of beach chairs, a beach towel, sunglasses, an umbrella, etc. in a corner along with some interesting seashore books. Place the books in a beach bag or a bucket.

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NOTE TO TEACHER

Background Information:
Mollusks are one of the largest groups of marine animals. They have been common in the seas for millions of years. There are five classifications of mollusks. They are squid or octopus, chitons, tusk shells, bivalves and univalves. The squid has no shell. Chitons and tusk shells are individual classifications and consequently they offer practically no shell variety. The hobby of shell collecting is stimulated most by univalves and bivalves.

Bivalves are two-shelled mollusks, the majority of which live in marine water. Powerful muscles hold their shells together. When these strong muscles relax, water enters the shell, bringing food and oxygen to the animal. The waste materials are washed out as the water leaves the shell. Most bivalves live in the sand or mud and move by means of a foot. Some of the more common species are clams, mussels, scallops, oysters, jingle shells and angel wings.

Univalves form the second largest group of mollusks. Most univalves have a single spiral shell. The shape of the spiral varies with each animal. Most univalves have a cover referred to as the operculum, that protects the animal when it is partially extended from the shell. Some common varieties of univalves are limpets, topshells, abalone, conchs, whelks and cowries.

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