Symbiosis Lesson Plan

Instructor: Joanne Abramson

Joanne has taught middle school and high school science for more than ten years and has a master's degree in education.

This lesson plan introduces high school students to the topic of symbiotic relationships. Using a video lesson, class discussion and a partner activity, students learn to recognize and describe mutualism, commensalism, parasitism and competition.

Lesson Objectives

By the end of this lesson, students will be able to:

  • define the term 'symbiotic relationship'
  • describe the different symbiotic relationships
  • recognize the different symbiotic relationships


1-1.5 hours

Curriculum Standards


Determine the meaning of symbols, key terms, and other domain-specific words and phrases as they are used in a specific scientific or technical context relevant to grades 9-10 texts and topics.


Analyze the structure of the relationships among concepts in a text, including relationships among key terms (e.g., force, friction, reaction force, energy).


Initiate and participate effectively in a range of collaborative discussions (one-on-one, in groups, and teacher-led) with diverse partners on grades 9-10 topics, texts, and issues, building on others' ideas and expressing their own clearly and persuasively.

Key Terms

  • Symbiotic relationship
  • Obligate symbiosis
  • Faculative symbiosis
  • Mutualism
  • Commensalism
  • Parasitism
  • Competition


  • Card stock
  • Envelopes
  • Paper cutter or scissors
  • Lined paper
  • Pens or pencils



  • Before class, think up at least two examples of each type of symbiosis mentioned in the video. For example:
    • The Maasai people in East Africa whistle to call the wild honeyguide bird. The honeyguide bird answers back, beckoning the honey hunters to follow. The bird leads them to an active beehive. The Maasai build a fire to smoke out the bees and extract the honey. They leave behind a piece of honeycomb to thank the honeyguide bird for its help. (Mutualism)
    • Whale barnacles attach to the side of baleen whales. The whales and the barnacles are both filter feeders, grazing on plankton for nourishment. The barnacles get a free ride to new feeding grounds while the whales are neither helped nor harmed by their hitchhikers. (Commensalism)
    • Cowbirds do not build their own nests. Instead, they locate nests of another species, kill the eggs currently in the nest, and then lay their own. The cowbird then leaves, separating from her young forever. When the nest's owner returns, the new bird incubates and raises the cowbird's young as though they were her own. (Parasitism)
    • Lions and hyenas in the African Serengeti share the same habitat and hunt the same prey. When hyenas outnumber lions, they will gang up and steal the lions' kills. Often lions and hyenas will attack each other's young in an attempt to control the opposition's population. (Competition)
  • Print all of the examples out onto card stock, but do not include the name of the relationship. Print out enough for each pair of students to receive a complete set.
  • Cut out each of the examples and place the entire set into one envelope. Repeat this until you have created enough envelopes for each pair to receive one.


  • Ask students to name animals that they see on a daily basis (dogs, pigeons, squirrels, flies, mosquitoes, etc.). As they name animals, write their responses on the board.
  • Lead the discussion so that there are examples of each type of symbiotic relationship on the board.
  • Once the list is long enough, ask students to think of why these animals live with us. (We feed dogs. Pigeons eat our trash. Flies were here first, we moved into their home.)
  • Point out that some of the relationships are positive, some are negative, and some don't really affect us one way or the other. (Also, point out that we have these relationships with plants, too: Trees give us shade and oxygen while poison ivy is less helpful.)
  • Explain to students that they just discussed organisms that have symbiotic relationships with humans. Symbiotic relationships are found throughout nature, and they will be learning more about them in today's lesson.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account