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Web of Life Unit
Mystery 5 of 6
Why do you have to clean a fish tank but not a pond?
Mystery 5 image
Web of Life Unit Mystery 5 of 6
Why do you have to clean a fish tank but not a pond?
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DISCUSS (1 of 2):

What do you think is wrong with the fish?

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DISCUSS (2 of 2):

What would you do to try to help the fish?

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DISCUSS:

How can fish survive in a pond if waste doesn’t get filtered out of the water?

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DISCUSS:

Can you think of anything that could help LOWER the amount of carbon dioxide in a pond?

Hint:

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1. DRAW: Sketch a model of the interactions in a pond ecosystem. To get started, write plants, decomposers, and pond animals on a piece of paper. (Don’t write them too close to each other, you’ll be adding things in between them). Then draw arrows and add labels to show all the things that connect them.

diagram sketch

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2. CHECK: Did you include waste, nutrients, carbon dioxide, and oxygen arrows in your model? If not, add arrows in for those too.

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3. HERE’S WHAT WE DID: Here’s what our model ecosystem looked like, but there are many ways to draw this and yours might look different.

diagram sketch

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If you need a natural stopping point!

Teachers: If you are short on time, this is a good stopping point. You can play the Big Fish ecosystem game in a future session.

If you’ll be playing another day, have each pair of students clip their cards, their Fish-o-meter, their pointer and their worksheets together with a binder clip.

If you’re continuing right now, advance to the next slide.

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Beginning Complete!

You've completed the Exploration & Activity!

If you have more time, view the assessment, reading, and extension activity in the optional extras.

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Optional Extras

Below are ideas for extending this topic beyond the Exploration & Activity you just completed.
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Resource: Set Up a Cold-Water Aquarium

A fish tank can be a great source of learning and pleasure. If you have the opportunity to add one to your classroom, these videos will help guide you. They show how to prepare a simple, cold-water tank, suitable for keeping a community of goldfish. Instructions on maintaining the tank, as well as choosing and caring for both the fish and their environment, are included.

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Resource and Activity: Make a Seaweed Salad!

Fish eat algae…and people do, too. Give your students a chance to get to know edible algae.

  • Did you know there were algae in your chocolate milk? This lesson, from the Smithsonian], lets students discover what common foods contain algae.
  • For a more in-depth exploration of edible algae, check out this website, from the California Academy of Sciences, with everything from lesson plans to recipes for seaweed salads.
  • For even more on different kinds of edible algae and how healthy they can be, check out this site.
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Videos

  • What’s in a drop of pond water? Watch this video (4:05) to see pond life under the microscope, and this one (1:13) for some pond-creature close-ups.
  • Two videos show the amazing complexity of life in the Florida Everglades. “The Food Chain” (4:49) introduces the flow of energy within the environment; “The Food Web” (3:07) connects some of those chains—all with up-close views of life in the swamp.
  • Decomposers are nature’s cleanup crews. Watch this video to see how they work. (3:18)
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Readings

Readings from Newsela are free with registration. They can be adjusted for reading level. A writing prompt and quiz questions are available for each reading.

  • Fish eat algae, but what happens when there’s too much of it? Read about one kind of problem algae that clogs river water with “rock snot.” (Grade 6)
  • A look at the worldwide ecosystem and the many relationships it contains. (Grade 5)
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Overview
Grade 5th
Topic Ecosystems & The Food Web
Focus Ecosystems & Matter Cycle
Print
Activity Prep

In this Mystery, students combine what they have learned about plants, animals, and decomposers to see how they interact in an ecosystem. In the activity, Pond Ecosystem Game, students first build a pond ecosystem that will support a sunfish. To succeed, they must make sure that carbon dioxide levels are healthy for both plants and animals. Then, students play a game called Big Fish where they compete to make a healthy ecosystem for a sunfish.

Preview activity

Number of students:
Scissors
30 pairs
Action Cards printout Print 8 copies
Big Fish Ecosystem Cards printout Print 15 copies
Check the Pond printout Print 30 copies
Fish-O-Meter printout Print 30 copies
Pick-a-Card/Discard Pile/How to Play printout Print 8 copies
Prep Instructions

In Part 1 of this activity, students will work in pairs. In Part 2 of this activity, students will work in groups of four to play the Big Fish game. Homeschool students can work on their own for Part 1, but will need a few friends in order to play the game.

Plan Your Time

Part 1 (building an ecosystem) takes 10 to 15 minutes. Part 2 (playing the game) takes at least 20 minutes.

You may want to divide this lesson into two sessions, stopping after Part 1 and continuing with the game at a later point. If you plan to do the activity in two sessions, the group game begins at Step 12.

Sort Materials for Part 1 and Part 2

Divide your materials into two piles.

For Part 1, you’ll need:

  • Half of the Fish-O-Meter printouts
  • Big Fish Ecosystem Cards
  • scissors
  • binder clips (optional)

For Part 2, you’ll need:

  • the rest of your Fish-O-Meters (so each student has one)
  • Check the Pond
  • Pick-a-Card/Discard Pile/How to Play
  • Action Cards
  • scissors

Planning for Two Sessions

If you want to do Part 1 and Part 2 on different days, you can keep materials organized by having each pair of students clip their cards, their Fish-O-Meter, their pointer, and their worksheets together with a binder clip at the end of Part 1.

When you are doing Part 2, start by giving each pair of students their materials from Part 1. Then have pairs get together to make groups of four and distribute the additional worksheets.

Overview
Grade 5th
Topic Ecosystems & The Food Web
Focus Ecosystems & Matter Cycle
Extensions