Ecological Interactions and Biodiversity of Kelp Forests Lesson Plan: Grades 3-5

Students learn how kelp forests play a vital role of the health of our global oceans


Kelp forests play a vital role in the health of our global oceans. These fragile biodiverse ecosystems provide the ideal ecosystem to look at ecological interactions among organisms, trophic structure, nutrient cycling, and overall ecosystem dynamics. Oftentimes students who live near the coast get to experience the rock intertidal zone, but rarely do students get a chance to explore and understand what lies beneath the vastness of the ocean. This lesson will allow students to explore the kelp forest using basic concepts in ecology without having ever left the classroom.


Students will engage in meaningful activities focused around kelp forest ecology and the role of kelp forests in maintaining the health of our local and global oceans.


In addition to the My Hero film you will need the following materials:

● Construction paper

● Scissors

● String

● Markers/colored pencils 

● Tape/Paper clips 

● Copies of worksheet provided


1. Drawing comparisons between the structure of kelp and that of a plant 

2. Looking at Energy flow and interactions within the kelp---students research one organism and create/add it to the kelp forest they created---students are asked to think about how many organisms would lose their habitat if the kelp didn’t exist, or if specific species didn’t exist.


What is a kelp forest and why is it important for ocean health?


This lesson is meant to give students a basic introduction into kelp forest ecosystem and basic ecological terminology. However there are several ways to extend or expand the lesson. 

If you live in an area where kelp is accessible it would be very beneficial to bring in a sample and allow students to examine it either macroscopically or microscopically. Looking at a kelp holdfast you will find multiple small critters and can further discuss biodiversity.



Kelp forests provide an important role in the health of our global oceans. They are found pole to pole in nutrient rich waters with water temperatures typically 20°C or less. Their dependence on light for photosynthesis restricts them to shallow coastal zones no greater than 40m in depth, an area often referred to as the subtidal zone. These kelp forests rapidly grow, sometimes gaining up to 30cm per day, and provide a rich biodiverse ecosystem for some of the 800 species that call it home. Each species occupies its own specific niche, or role within the environment. The balance of these interactions is what keeps the kelp forest healthy and in balance with the surrounding ocean environment. With more and more human exploitation of our ocean resources, our kelp forests and the species that reside within them have become threatened. To maintain their existence humans have resorted to restoration efforts.


Lesson Plan Activities


1. Q. What is a kelp forest and why is it important for ocean health? 

● Have students think pair share 

● Whole class share out 

● Read overview and background provided 

2. Q. How does kelp get energy to grow? 

● Discuss photosynthesis briefly 

3. Review or introduce the following terms: 

● Ecology 

● Ecological Interaction (within species, among different species), Interdependent Relationships 

● Ecological Niche/Role 

● Biodiversity 

● Food Web



4. Read the background provided on kelp forests. 

5. Watch the film: The Kelp Lady (9 min) 

6. Compare the kelp forest to a local ecosystem such as a forest or savannah and discuss biodiversity.


Practice and Application:

7. Exploring structure and function of kelp: Have students complete the plants vs. kelp worksheet

● Have them make observations about the structure of the plant portion first—labeling: leaves, roots, stem. 

● Walk them through the kelp part labeling kelp: stipe, blade, holdfast, and float. ● When they are finished labeling have them draw a dotted line between similar structures on plant and kelp: (holdfast-roots; blade-leaf; stipe-stem). Go over the correct answers at the end. 

8. Extension: Create a kelp forest: Give each student a piece of construction paper and based on their kelp diagram cut out a blade of kelp. If you are worried about size and shape uniformity you can provide a template. Attach all blades to string to create a large length(s) of kelp. Eventually stringing this to the ceiling

9. Looking at Energy flow and interactions within the kelp: students research one organism and create using construction paper and markers/add it to the kelp forest they created---students are asked to think about how many organisms would lose their habitat if the kelp didn’t exist, or if specific species didn’t exist. 

10. Class discussion regarding the role of kelp and the role of individual organisms within the kelp forest

11. Provide any feedback needed. 

Q. Were students able to successfully create their kelp forest? 

Q. Did students gain knowledge about the differences and similarities between the structure of kelp and the structure of plants? 

Q. Did students gain insight into the diversity of the kelp forest ecosystem?

12. Review the essential questions and vocabulary. 

13. Install kelp forest and keep in the classroom for review. 

14. Have students share out about local Eco Heroes in their lives and communities similar to Nancy Caruso in the film (for a longer assignment students could produce a video, art piece, or short story)


Adapted from the SIOP Model by Echevarria,Vogt and Short, 2008

Created By: Lauren Fieberg, Sage Hill School (revised 2020)


Organizer created on 7/21/2020 1:54:12 PM by Laura Nietzer

Last edited 7/21/2020 2:11:18 PM by Laura Nietzer