Oysters & Organisms Lessons



Class Periods




Subject Areas


Students will investigate the anatomy and morphology of an eastern oyster through observation and dissection.


  1. Dissect an oyster.

  2. Observe structures of oyster’s anatomy and make inferences.

  3. Sketch the oyster and accurately label it.

  4. Identify major body parts and structures of the oyster.

  5. Design an oyster predator that takes advantage of the oyster’s anatomy and morphology.

Materials and Resources


Live adult oysters (can be purchased at Fresh Direct or Whole Foods) Live spat-on-shell (from your Oyster Restoration Station or Billion Oyster Project) Hand lenses Dissection trays or plastic plates Oyster shucking knife and glove Dissection tool Dissection microscope or hand lenses Calipers

Before you get started

Tips for Teachers

Consider partnering with BioBus for access to a classroom set of microscopes (biobus.org) This activity works best in groups of 2-3 students Consider how and when you will shuck the oysters. If possible, get enough oysters to have a set that is alive and closed and a set that is shucked shortly before students arrive in class. Tissues should be carefully dissected from one shell and remain attached to the second shell. Set the removed shell on top of the exposed body. Invite some volunteers into your classroom to help shuck oysters. Recycle your oyster shells in the estuary when your lesson is complete!




Oysters have a relatively simple anatomy that is both reliable and efficient.  Taking a look at the oyster’s anatomy gives us some insight into how an oyster functions within its environment.  One of the most important features of the oyster’s morphology is that they are filter feeders. They eat by drawing in water over their gills with the help of cilia. Suspended plankton and particles are trapped in the mucus of the gills, and from there are transported to the mouth, where they are eaten, digested, and finally expelled. An adult oyster can filter up to 50 gallons of water per day!

Instruction Plan


  1. Students get into small groups

  2. Each group gets a live, adult oyster.  This is an oyster that is about 2 inches long, with two shells that are closed tightly.

  3. Students look at the oyster carefully and either have a discussion or do a short piece of writing based on the following questions:

    • What does an oyster look like on the outside?  What do you think it looks like on the inside?  What body parts do you think it has in there?  

    • Think about human anatomy and fish anatomy. Does the oyster have eyes, ears, mouth, lungs, heart, etc?  (You may want to display or hand-out the diagrams below.)  Which body parts do you think the oyster needs to survive?

Fish Anatomy



Human Anatomy




Explore the Oyster Reef Organisms

  1. Get into a group of 2-3 students.

  2. Students get the Oyster Anatomy Worksheet  and the Oyster Reef Organism Key

  3. Each group gets a spat-on-shell on a dissection tray and adds their live adult oyster.

  4. Observe the spat-on-shell and look for other organisms (e.g. worms, barnacles, or crabs).  Remove organisms and observe with hand lens or microscope.  

  5. Sketch, describe and label the organisms.  Use the Oyster Reef Organism Key to help you identify them.

  6. Make an inference: why are these organisms found among oysters?

Explore the External Anatomy

  1. Examine the outside of an oyster.

    1. Identify the two shells and compare them.  Think about the size, thickness and shape of the two shells.  

    2. Why might the two shells be different?  What part of the oyster shell do you think was attached to the reef?  Why?

    3. Why does the oyster have a hard exterior?  Why does it have two shells? How might this help the oyster?

  2. Measure the length of the shell the “long way” and record your result.  Why do you think we need to measure the size of the oyster?

  3. Sketch and describe the external anatomy of the oyster.  What do you see?  Make some inferences: why does the outside of the oyster look this way?

  4. Get an Oyster External Anatomy Diagram.  

  5. Try pulling the shells apart.  What do you think holds the shells together?

  6. Do you see any evidence (or artifacts) of other organisms on the oyster’s shell? What do you see?

  7. Compare your sketch to the diagram.  Label your sketch with the appropriate structure names.

  8. Review the external anatomy with the whole class.  Use the first 16 slides of the Oyster Anatomy Slideshow. There are “presenter notes” included that provide some additional information about the anatomy.  You may also want to give a print-out of the slideshow with or without the presenter notes to each group.

Explore the Internal Anatomy

  1. Get a shucked oyster on a dissection tray.

  2. Describe the oyster’s body. Look at it! Smell it! Touch is gently! Is the tissue hard or soft?  What color(s) is the tissue? What does it smell like? Can you see or feel bones?  Is there a head? Do you see blood?

  3. Sketch the internal anatomy of the oyster.  What do you see?  Make some inferences: what are the functions of the structures you see?

  4. Get an Oyster Internal Anatomy Diagram.

  5. Compare your sketch to the diagram.  Label your sketch with the appropriate structure names.

  6. Review the internal anatomy of an oyster with the whole class. Use the second half of the Oyster Anatomy Slideshow. Again, there are “presenter notes” included that provide some additional information about the anatomy.  


  1. This portion of the lesson will need to be completed in a second class period.

  2. Tell students: Now that you’ve looked carefully at the internal and external anatomy of a real oyster, we are going to make our own oyster and practice learning the names of the different parts of the anatomy.


Make a paper model of an oyster using the following documents:

Oyster Anatomy Paper Model Directions

Oyster Anatomy Paper Model Cutouts


  1. Students will design their own organism that is a predator of the oyster. The predator must live on or near the oyster reef.  Students will sketch and describe their oyster predator.  Students must specifically refer to the oyster’s anatomy as they describe how their organism preys on the oyster.  

  2. What challenges or barriers must the predator overcome in order to prey on the oyster? How will the predator take advantage of the fact that the oyster is sessile? What part of the oyster will the predator eat? Why?