Title – Introduction to the Garden Snail

By – Ruby Starleper

Primary Subject – Science

Secondary Subjects – Math, Art

Grade Level – 2-4

I. Objective:

• Identify parts of the snail’s external structure.
  
• Understand the environment necessary for the snail to survive.

II. New Mexico Science Standards:

• Strand II: Content of Science.

  • Standard II (Life Science): Understand the properties, structures, and processes of living
    things and the interdependence of living things and their environments.

    • K-4 Benchmark I: Know that living things have diverse forms, structures, functions, and
      
      habitats.
      • Grade 2:
        1. Observe the various physical characteristics of garden snails.
           
        2. Observe and describe the common garden snail’s environment.
           
        3. Know that snails are invertebrates, mollusks, and gastropods.

    • K-4 Benchmark III: Know the parts of the garden snail and its functions.
      • Grade 2:
        1. Identify various body parts of the garden snail (e.g., foot, eyes, feelers, mouth)
           
        2. Know that various foods are necessary for the specific body parts and functions to work properly (e.g., calcium for a strong shell, leafy vegetables for water and nutrients)
           
        3. Identify functions of the garden snail’s body parts (e.g., respiratory, touch, smell)

III. Materials:

Observation Station: two garden snails, magnifying glass, two clear plastic cups,

snail worksheet

(http://www.kiddyhouse.com/Snails/snailclips/snailanatws.gif)
.

Identification Station: two model snails (see instructions at bottom of lesson plan), body part labels on paperclips (at bottom of lesson plan), and a pencil or pen.

Snail Game Station: six snail game pieces, one game place mat, two dice (instructions to make snail game at bottom of lesson plan).

Craft Center (Optional activity): six foam sheets of various colors, several glue sticks (instructions to make the snail craft at bottom of lesson plan).

IV. Anticipatory Set:

To grab the students’ attention, hold a snail in your hand and walk slowly around the classroom, allowing all the students to observe. While walking, introduce the characteristics of garden snails.

V. Procedure:

After introducing the garden snail to the students, set up the following stations:

Observation Station: Transfer snails from their plastic tank to clear, plastic cups to allow a group of children to observe the snail’s movements, eating habits, and body structures. After observing, the children will complete their worksheet, labeling the snail’s body parts.

Identification Station: Students will test their listening skills and label various external body parts as possible on the model snails, using the paperclips with body part labels.

Game Station: The students will realize how slow snails move when they “race” their clay snails (game pieces). This activity will use math skills, as well.

Craft Center (optional): The students will paste several circles onto the snail’s foam body to create a beautiful shell and whorl. The students will learn that the shell is a complex structure, and it has several “swirls” that make up the whorl.

VI. Background Information:

Characteristics of Snails:
Snails can be found in gardens, ponds, and in the sea. They
belong to a group of soft-bodied animals, called mollusks, which are related to oysters, clams, and octopuses. Characteristically, they have unsegmented bodies. Normally, their soft bodies are protected by a hard shell. The scientific name for the garden snail is helix aspersa. It is a gastropod, which in Latin, gastro means stomach and pod is foot – “a belly-footed animal.” The body of a snail is long, moist and slimy. The shell protects its body and when it is disturbed or threatened, it withdraws or pulls itself into its shell. The snail also retreats to its shell and seals the entrance in dry weather to protect its body from drying up. It does not like hot or dry conditions. They prefer moist and humid conditions and do not like bright days. A snail is most active at night and on cloudy days. It does not like the sunshine very much. During cold weather, the snail hibernates in the ground.

Eating habits:

Snails have a radula in their mouths for grinding food. The radula is like a rough tongue and is similar to a file with rows of tiny teeth. Snails eat mostly living plants as well as decaying plants. They also enjoy fruits and succulent plant bark.

Movement:

The snail moves by creeping on a flat “foot” underneath the body, the sole. The band of muscles in the foot contract and expand and this creates a rippling movement that pushes the snail forward. The “foot” has a special gland that produces slimy mucus to make a slippery track. The slime comes out from the front and hardens when it comes into contact with air. The snail is able to move on very sharp pointed needles, knife, razors and vines without being injured because the mucus-like secretion helps to protect its body.

Reproduction:

The snail is both male and female. Therefore, it can produce sperms and eggs at the same time! An animal which is both a male and a female is called a hermaphrodite. The brown garden snail lays about 80 spherical shaped white or yellowish colored eggs at a time into the topsoil of the ground. It can lay eggs up to six times a year. Snails take about 2 years to become adults.

Enemies:

Snails have many natural enemies. They are the ground beetles, snakes, toads, turtles, and birds including chickens, ducks and geese.

Background information taken from


http://kiddyhouse.com/Snails/

Precautions:

• 
  Although some snails are edible, garden snails are not.
  
  If ingested, the person may become very sick, perhaps even die. If the children handle the garden snails, ensure they wash their hands immediately after handling them.

• 
  While the snail has a hard shell to protect it, the shell is still fragile.
  
  If dropped, the snail’s shell will break and make it vulnerable to diseases and predators. Stress to the students the importance of handling the snails carefully and warn that kicking or stepping on snails may possibly kill the snails.

• 
  Snails must live in humid, moist places to survive.
  
  If their bodies dry out, they will die. For this reason, garden snails will die if they come into contact with sodium-saturated places or materials. Explain to the students that salt will kill land snails because salt draws out all the moisture in their bodies. It is similar when people spend the day at the beach. The salt in the water and sand dehydrates our bodies. That is why people always get thirsty at the beach.

VII. Evaluation:

• The snail labeling worksheet can be completed in class to evaluate the student’s ability to identify the snail’s characteristics.
• The hands-on activity involving identifying the body parts on the snail models can also serve as an evaluation tool for the teacher.
• Students will identify the snail’s characteristics/body parts with 80% accuracy.

VIII. Homework:

• Students can take home the Snail Crossword Puzzle to become more familiar and practice using the vocabulary words introduced in the classroom lesson.

• Snail Crossword Puzzle –
  You may find several crossword puzzles by searching the internet. I found a great one on
  

  http://www.geocities.com/sseagraves

Observation Station:

Observing the Snail Student will observe the garden snail’s physical characteristics. Use the magnifying glass to take a better look at the snail’s tentacles and mouth. Can you identify its body parts? Test your knowledge by completing the worksheet provided. You may refer to the poster board for assistance. Handling Care: Before and after handling, please wash your hands thoroughly. Please handle snails with care. They are very fragile. Although they have hard shells, their shells will break if dropped, kicked, or if you step on it.

Identification Station:

Labeling the Snail Model There are seven (7) body parts/structures to identify on each snail model. Not all labels will be used. Both models contain the same parts to identify. Students will divide into two (2) subgroups. Insert labels in the appropriate areas identified by red circles. After labeling the model snails, fill out the worksheet provided.

Game Station:

Snail Game 2-6 players 1 game piece per player The Snail Game shows students that it can take a snail a long time to get to its destination. Begin at the “ Start .” Place all game pieces in the “Start area.” Each player will roll the dice , one at a time. Move the game piece towards the “Finish,” however many spaces the dice reveals. The first player to reach the “ Finish ” line is the quickest snail and can be crowned “King Speedy.”

Art Center (optional activity):

Creating Your Own Snail Each student will make one (1) snail. After creating your snail, discuss with your group how simple or complex you think the snail’s shell is. Instructions: 1. Place snail body in front of you. 2. Take one large circle and glue it to the “hump” on the snail. 3. Take a medium circle and glue it to the center of the large circle. 4. Glue a small circle in the center of the medium circle. 5. Glue a tiny circle to the center of the small circle. 6. Glue eyes to the top of the snail’s tentacles.

1. Snail Models
   • Snail Model Materials:
     
     

     • 1 small balloon
       
     • 1 big balloon
       
     • several strips of newspaper
       
     • flour
       
     • water
       
     • 2 pipe cleaners
       
     • 1 paper plate
       
     • tape
     • 11 labels
       
     • 11 paperclips

   • Procedure for making Snail Model:
     1. Inflate the big balloon for the shell area to the desired size.
        
     2. Inflate the small balloon for the head to the desired size. Tape both balloons together. The bottom of the small balloon should be level with the bottom of the large balloon.
        
     3. Fold one pipe cleaner in half and tape to the top of the small balloon. These will be the large tentacles.
        
     4. Cut a pipe cleaner in half. Fold it in half and tape to the head, about one-inch below the large tentacles. These will be the feelers.
        
     5. Cut flat part of paper plate in a tear drop shape. Position the body of the snail (large balloon) over the paper plate and tape.
        
     6. To make the paste, mix about one cup of flour to approximately one cup of water. The paste should not be too thick or too runny.
        
     7. Dip one strip of newspaper in the paste, remove excess paste and place on large balloon. Repeat step 7 until entire snail is covered in newspaper. Do not cover tentacles in newspaper.
        
     8. Allow to dry for 2 days. Paint desired color when dry.

   • Procedure for making Labels for Snail Model:
     1. Partially open paperclip so that one end is extended.
     2. Cut each label below (or hand write your own labels) and paste onto the rounded end of a paper clip. The extended end of the paperclip will be inserted into a small hole that you make in the snail model.

        Foot	Skull	Whorl	Mouth	Feelers
        Tentacles	Soft body	Toes	Ears	Radula

     3. Note: The skull, toes, and ears are not parts of the snail. They are intended to be “tricky.”

2. Snail Game
   
   • Game Board Materials:
     • 2′ x 5′ fabric, any color
       
     • 2′ x 1/4″ strips of black fabric

   • Procedure for making Game Board:
     1. Glue strips of black fabric onto 2′ x 5′ fabric in checkered pattern with hot glue.
        

   • Game Piece Materials:
     • Sculpey clay – any color or white to paint afterwards.
       
     • Paper clip
       
     • 2 pieces of pipe cleaner (1/2″ long) for each game piece

   • Procedure for making Game Pieces:
     1. Soften clay by kneading it.
        
     2. Roller a lighter color (for the body) into a ball, then roll in between hands to make long “strips” (like snakes).
        
     3. Cut strip into 1½ – pieces to use for the snail body. Form one end at a rounded point for the tail. Tilt the end for the head slightly upward.
        
     4. Follow steps 2-3 using a darker color.
        
     5. Cut strips into 4″ for the shell.
        
     6. Lay strip down, vertically. At the end closer to you, roll end towards the opposite end of the clay.
        
     7. Place roll on top of the snail body and push together softly.
        
     8. With a paperclip, poke two holes for the tentacles on the head of the snail. Do not add pipe cleaner pieces.
        
     9. Bake at 350 degrees for 15 minutes. Remove from oven and let cool.
        
     10. Add a dab of glue to one end of each pipe cleaner and insert into holes on the snail’s head.
         

   • Dice Materials:
     • You can easily make two dice for the Snail Game by using four, small milk cartons (the kind the children drink at lunch).
     • Ensure the cartons are empty, clean and dry.

   • Procedure for making Dice:
     1. Cut off the triangular tops of each carton.
        
     2. With the open end of one carton facing the open end of another carton, insert one carton into the other. Tap the cartons gently so the top is flush with the bottom of the carton.
        
     3. Repeat steps 1 and 2 to make a second die.
        
     4. Cover each die with colored contact paper or construction paper.
        
     5. Draw your own black circles on each side of the die, but only make 1 or 2 circles on each side. Remember, your snails move slowly, so they can’t move too fast in the game.

     Now you have your complete Snail Game. Have fun!!

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Ruby Starleper

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