Lakeville: Session 2

Components of an Ecosystem

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INTRODUCTION: Session 2 introduces the ecosystem component for the Lakeville unit OR it can be used as a stand-alone introduction to the components commonly found in a Florida freshwater habitat. Each student is given an opportunity to role-play (at least) six inhabitants of the ecosystem and contemplate the complex relationships found within its food web. Classification concepts are also practiced when students are asked to categorize their role(s) in the habitat as an aquatic, terrestrial, native, non-native, or invasive species and identify their positive and negative attributes.


  • What are the components of an ecosystem?
  • What are some of the factors that make ecosystems complex?

SUBJECTS: Science, Math, Social Studies, Language Arts (See NGSSS)


CONCEPTS (Science Big Ideas): ecosystems, keystone species, food web, disturbed areas, social and economic concerns and their effects on society, life cycle reproduction, animal life spans, plant uses and characteristics, nutrient uptake, alternative sources of energy, oxygen levels

OVERALL TIME ESTIMATES: One 45 minute session

LEARNING STYLES: Visual and auditory

VOCABULARY: [Also see keywords chart and definitions] advocate, angler, aquatic plant, brackish, bulbils, cesspool, commerce, developer, ecological significance, ecosystem, economic importance, emersed, endangered species, floating-leaved, habitat, herbivore, invasive, keystone species, mangrove, native, non-native, noxious weed, poached, priority, pros and cons, regulation, rhizome, scavenge, spores, stolon, submersed, suburban, turion, terrestrial, tuberous, weed

SESSION SUMMARY: Students learn about native, non-native and invasive plants and animals found in Florida freshwater ecosystems by taking turns in role playing activities. Each student will practice representing three individual citizen roles (e.g., as a developer, restaurant owner, boater, angler, factory owner, farmer, etc.) and three different "organism" roles (plants or animals). Analytical skills are challenged when students are asked to analyze and identify, in writing and in class discussion, personal priorities they may have as a citizen in the community or an organism in the habitat.

STUDENT LEARNING OBJECTIVES: Students will be able to…

  • Identify different components of a Florida freshwater ecosystem.
  • Identify at least three native, non-native or invasive plants or animals that live in Florida and discuss their role in the habitat.
  • Describe some of the complexities and interconnectedness of an ecosystem.
  • Identify and express different points-of-view of the various stake-holders living in an ecosystem and the surrounding community.

1. Large habitat poster (or projected picture)

2. CITIZEN Role Cards

  1. Angler
  2. Boater
  3. Developer
  4. Farmer
  5. Lake resource manager
  6. Politician (City or County Commissioner)
  7. Nature lover
  8. Owner of a manufacturing company (aquatic products)
  9. President of local jet ski or water ski club
  10. Restaurant owner (business depends on recreational lake users)
  11. Retiree (grandmother/grandfather)
  12. Wild card – student decides what role they want to play

3. Organism Role Cards

Native Plants Non-native Plants Invasive Plants Native Animals Invasive Animals
1. pickerelweed
2. duck potato
3. eel grass
4. fragrant water lily
5. duckweed
6. poison ivy
7. cat-tails
1. coconut palm
2. hibiscus
3. Canadian water weed
4. orange tree
5. peanut plant
1. air potato
2. hydrilla
3. water hyacinth
4. Old World climbing fern
5. tuberous sword fern
6. wild taro
1. American alligator
2. gopher tortoise
3. manatee
4. snail kite
5. largemouth bass
1. fire ants
2. Gambian pouch rat
3. iguana
4. monk parakeet
5. Island apple snail
6. Burmese python
7. sailfin catfish

4. Citizen Role Analysis Worksheet

5. Organism Role Analysis Worksheet


  1. Download materials from website OR borrow
    Lakeville kit
  2. Review materials in advance, including the vocabulary
  3. Post the large habitat scene in the classroom and prepare materials to distribute.

PART 1 ~ Discuss the meaning of ECOSYSTEM (5 minutes)

  1. Display the large habitat scene, which has been created for this activity. Ask students what they see in the habitat (a body of water, meadow, wooded area etc.) Explain that it is picture of an ecosystem—without any of the inhabitants visible. Their job is to make decisions as to which plants and/or animals will live in the ecosystem.
  2. Discuss the components of the ecosystem including the physical features and the biological community we would expect to find here (i.e. plants, animals, humans, bacteria, etc).
    3. Discuss characteristics of human residents and the roles they have in the ecosystem and the food web.

PART 2 ~ Introduction to Citizen Roles (15 minutes)
There are 12 specific citizen roles provided for this activity. See list on page 2. Recommendation: Students work in pairs.

  1. Distribute Citizen Role cards. Explain that each card contains the name of a citizen role one might find in a community (e.g., angler, developer, farmer, retiree, etc.). Next, point out that each card also contains a brief description of the priorities this citizen may have.
  2. As a class discussion, ask students to take turns reading the brief description of each role and the priority provided on the card. Be sure to mention that the "priorities" certainly don’t apply to all anglers, farmers, developers, etc. They are only a starting point for discussion.
  3. Distribute Citizen Role Analysis Worksheets. Explain that in a minute, they will be asked to list three things they do want or do not want in their ecosystem, based on the priorities given on their role card and also based on their own knowledge about the citizen role.
  4. Teacher — Choose a Citizen Role card as an example and read citizen's priority. As a class, brainstorm a list of what that citizen may or may not want in their local habitat. Ask students to record their information on their Citizen Role Analysis Worksheet under Citizen Role #1.
  5. Ask students to trade Citizen Role Cards with the group next to them. With their new cards, allow students two minutes to brainstorm ideas and record what they may or may not want in their habitat. Ask them to record their analysis in the space provided on Citizen Role Analysis Worksheet, under Citizen Role #2. Remember: priorities provided on the cards are simply a starting point for discussion. Students may change the priorities associated with their role but they need to be clear and consistent in their discussion and writing activities and be able to justify their responses.
  6. Redistribute Citizen Role Cards AGAIN, so everyone has a different card and repeat the brainstorming and recording of ideas on their Citizen Role Analysis Worksheets. This way, each student experiences three different citizen personalities in their local community – ecosystem.
  7. As part of a class discussion, ask each student to share at least one citizen role, along with their point-of-view by stating one thing they may or may not want in their environment and why. Allow each student to share at least one Citizen's opinion (time permitting).
  8. Collect Citizen Role Cards.

PART 3 ~ Introduction to Organism Roles (20 minutes)
Thirty plant/animal Organism Role Information Cards have been developed for this activity. See Page 2. Available on-line: Recommendation: Students work in pairs.

  1. Distribute Organism Role Cards. Explain that each card contains information about a specific "organism" one might find in a Florida freshwater ecosystem. Familiarize students with the location of key information on the card (common and scientific name and status as a native, non-native or invasive species). Students will use the information to learn about their anticipated "behavior" in an ecosystem.
  2. As part of a class discussion, ask each student to read the name of their species and classify it as… a plant or animal / aquatic or terrestrial / native, non-native or invasive.
  3. Distribute Organism Role Analysis Worksheets. Explain that in a minute, they will be asked to list three positive and three negative attributes (i.e., the pros and cons) each organism may have based on the information on their Role card.
  4. Teacher: As a class, read through one Organism Card as an example. While reading the organism's information to the class, ask the students to take note of the pros and cons that may be associated that organism. As a class identify the pros and cons for the sample organism and record the information on the Organism Role Analysis Worksheet, under Organism #1.
  5. Ask Students to trade the Organism Role Cards with the group next to them (individually or one card per pair of students). With their new card, allow 4-5 minutes for students to read the card and record the positive and negative attributes on the Organism Role Analysis Worksheet.
  6. Ask students to switch information cards AGAIN so that every student or pair has a different card. With this new card, once again read, role-play and record the positive/negative attributes.
  7. In a class discussion, allow each student to share the traits of at least one organism. This way, all of the students will become aware of all the potential organisms in the habitat.
  8. Collect Organism Cards.

PART 4 ~ Wrap Up!
To wrap up the activities and further reinforce comprehension of the complexity of an ecosystem, ask students to discuss and write a response to the following question:
"How did this activity help you to better understand the definition of an Ecosystem? Give specific examples."


  1. Teaching Points about native, non-native and invasive plants are available in the Resource section of our website
  2. The National Invasive Species Council published an official "White Paper" with clear and concise definitions of the terms "non-native" and "invasive" species, along with many examples of the damage being done by invasive species. See "ISAC Definitions White Paper" at
  3. Additional information about invasive plants in aquatic ecosystems:


  1. Collect and review the Citizen Role Analysis Worksheets and Organism Role Analysis Worksheets (Objectives #1, #2 and #3)
  2. Students create their own Citizen or Organism Role Card, writing and presenting a 'biography' of a native, non-native, or invasive plant or animal—or a local citizen—and providing the folowing information (see text box): (Objectives 1, 2, 3, 4)


  1. Understanding Invasive Aquatic Plants (Activity Book) — PDF
  2. Aquatic Plants: The Underwater Forests of Lakes and Rivers – PDF – A "stand alone" activity book about freshwater ecology
  3. Images and information on plants, see