Water is Life


This lesson introduces students to krill, their importance in ocean ecosystems, and the physical structures that make up the krill body. The students will then use the principles of a "floater" species and design their own krill, hopefully having a class competition to see who can build a better krill.

Students will understand the importance of krill in an oceanic ecosystem. The students will also learn about the physical characteristics of krill as a floater species and then be able to design a new species.

##Lesson Preparation
This is an excellent introductory lesson to oceanic food webs, and the importance of micro flora and fauna in ocean ecosystems. This lesson is also an excellent starting point prior to teaching about zooplankton and phytoplankton.

DAY ONE: Students will learn about krill and their importance in an oceanic ecosystem. Review food webs and chains with oceanic species. Students and teacher will build an oceanic food web, with each student representing a different ocean species (Ocean Food Web Activity attached).

DAY TWO: Students will be introduced to the physical structure of a krill and will discuss its locomotion. This is also a time when you could introduce the concept of climate change (side lesson). Students will discuss as a class how krill move throughout the water column, as well as within the ocean ecosystem in which they live.

DAY THREE: Students will build a model of a krill. They will answer questions as to the krill's structure and ability to adapt and survive but not be invasive.

DAY FOUR: Students will have a competition to see whose new krill species will be able to: float upright, be able to move within the water column and laterally across the surface.

* Class discussion on climate change and how an increase in ocean temperature can adversely affect krill, and in turn other oceanic species.
* Discussion on physical adaptations different species have to be able to survive in their unique ecosystems.
* Graph krill populations and how they are changing over time. http://commons.wikimedia.org/wiki/File:Antarctic_krill_catch.png

The following images can be either electronically displayed for student learning, or printed out for individual student use. All images and graphics were found on the Internet, with the sources cited.

Krill Images:

Additional Images:
http://animals.nationalgeographic.com/animals/invertebrates/krill.html (krill information)
http://www.coolantarctica.com/Antarctica%20fact%20file/wildlife/krill.htm (Antarctic krill)
http://en.wikipedia.org/wiki/Antarctic_krill (great krill facts)

Students will be assessed on their ability to complete the ocean food web activity. There will be a grading rubric for the structure of their new krill species, and students will be asked to write a two paragraph summary on why the krill is such a vital part of ocean food webs, and hopefully include how climate change will adversely affect this species (through use of the extension).

Jillian Worssam, jworssam [at] hotmail.com



  • K-4
  • 5-8
  • Content Standard A: Science as Inquiry:
  • Content Standard C: Life Science:
  • a. Abilities
  • b. Understandings
  • a. Characteristics of organisms
  • c. Organisms and environments
  • Content Standard C: Life Science:
  • a. Structure and function in living systems
  • e. Diversity and adaptations of organisms

Resource Details

Author(s): Jillian Worssam


  • Ocean Food Web Activity
  • Krill handouts
  • Pond, or water source to test new krill species
  • Internet access
  • Yarn
  • Animal cards
  • Assorted art materials for construction of new krill (balloons, pipe cleaners, sponges, string are just a few suggestions)


Arctic, Antarctic

Completion time

Less than a week

Grade Level

Elementary and Up


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Life Science | Ecology | Oceanography | Polar Science | General Polar Science