The Arizona STEM Acceleration Project

Building a Closed System Terrarium

Building a Closed System Terrarium

A 3rd, 4th, 6th and 7th grade STEM lesson

Tasha Weeks

April 14, 2023

Notes for teachers

• You could do this together, step by step or give them all of the materials and information needed to do it by themselves.
• Could be a group activity or an individual activity so each student can take home a terrarium
• Succulents and Cacti will not work in closed system terrariums
• Opportunity to show students how to propagate spider, ivy and other plants that can possibly go into the terrarium. You could also have students buy their own plants.
• Great online water cycle interactive resource: https://water.usgs.gov/edu/watercycle-kids-adv.html

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List of Materials

• Large mason jar with cover (or any type of glass jar with a cover)
• Small rocks (aquarium rocks work perfectly)
• Activated Charcoal (optional)
• Soil
• Plants that grow well in a closed terrarium (succulents and cactus will not work)
• Moss (living or fake…optional)
• Decorations (optional)

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1. 1 inch layer of rocks on the bottom
2. 1 tsp of activated charcoal (optional)
3. About 3 inches of soil
4. Put the plants in the soil
5. Add moss
6. Add any decor
7. Use a spray bottle to spray water in the terrarium
8. Close the lid
9. Watch the water cycle in action

Standards

3rd Grade:

3.L2U1.7 Develop and use system models to describe the flow of energy from the Sun to and among living organisms.

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4th Grade:

4.E1U1.8 Collect, analyze, and interpret data to explain weather and climate patterns.

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6th Grade:

6.L2.U1.13 Develop and use models to demonstrate the interdependence of organisms and their environment including biotic and abiotic factors

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6.L2U1.14 Construct a model that shows the cycling of matter and flow of energy in ecosystems.

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7th Grade:

7.E1U1.5 Construct a model that shows the cycling of matter and flow of energy in the atmosphere, hydrosphere, and geosphere.

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Science and Engineering Practices

• ask questions and define problems
• develop and use models
• plan and carry out investigations
• analyze and interpret data
• use mathematical and computational thinking
• construct explanations and design solutions
• engage in argument from evidence
• obtain, evaluate and communicate information

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Objectives:

Today you will build a closed system terrarium to be able to observe the water cycle in action.

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I can explain what the water cycle is.

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I can create an ecosystem in a jar.

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Agenda (60 minutes)

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Opening Discussion “Ask”: 10-15 minutes

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“Imagine/Plan”: 10-15 minutes

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Build Terrarium: 15 minutes

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Clean-up: 5 minutes

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Debrief “Improve”: 10 - 15 minutes

ASK

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What is the water cycle?

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How do you think the water cycle is represented in a terrarium?

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What is the water cycle? How do you think the water cycle is represented in a terrarium?

1. We add water to the jar and close the lid
2. Soil absorbs the water
3. Roots uptake the water
4. Veins carry the water to the leaves
5. Sun heats up the jar
6. Water from the soil and plant’s leaves evaporates (transpiration)
7. Condensation forms on the glass and lid
8. The water droplets become larger and fall back to the soil starting the process over again (precipitation)

The plant survives due to sunlight, creating its own water cycle and aerobic bacteria that eats the dead plant matter creating more nutrients for the soil. Bacteria also helps by using up the oxygen and creating carbon dioxide for the plants to be able to photosynthesize. Biotic and abiotic factors make up ecosystems. Biotic factors are the living things like bacteria, plants and animals. Abiotic factors are the nonliving things like air, soil and water.

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Vocabulary

Biotic - Living things in an ecosystem. Examples include bacteria, plants and animals

Abiotic - Nonliving things in an ecosystem. Examples include the atmosphere, water and soil

Plant uptake - the plant’s roots move water from the soil to the plants with capillary action

Transpiration - plants lose water vapor through the stomata

Evaporation - water turning to vapor, then floats up. Heat is needed.

Condensation - Caused by temperature changes warm to cool, vapor turns to liquid again

Precipitation - Any liquid or frozen water that falls from the atmosphere

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Fun fact:

There is no water lost in the system - the water on Earth is the same water from millions of years ago

IMAGINE

Use questions to prompt thinking

• How is the water cycle represented in a terrarium? What would cause it to work or not work? What is living and nonliving? The pictures don’t have to look real, as long as they know what they mean…
• How will you see evaporation, transpiration and precipitation? How will the setup of your terrarium affect the water cycle?

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PLAN

• Look at your sketches and ideas.
• Which one seems like the best idea to try?

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Choosing between ideas and compromising can be difficult!

• Choose one idea, or synthesize multiple ideas
• How will you begin? How will you accomplish your goal within the constraints given?

CREATE & TEST

• Did you add enough water?

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• What worked? What didn’t? (check back in question - after time to observe)

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Hands-on Activity Instructions

List of Materials

• Large mason jar with cover
• Small rocks
• Activated Charcoal
• Soil
• Plants
• Moss
• Decorations

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• 1 inch layer of rocks on the bottom of jar (could be tilted on side or standing up right)
• 1 tsp of activated charcoal
• About 3 inches of soil
• Put the plants in the soil, completely cover roots and bottom of the plant
• Add moss
• Add any decor
• Use a spray bottle to spray water in the terrarium, make sure the soil is a little wet, but not soaked. Too much water will kill the plant and cause mold
• Close the lid
• Watch the water cycle in action

IMPROVE

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• What else could you try or do differently?

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• Imagine, plan, and build a new terrarium, can you improve it?

Assessment

Did the students participate in making a terrarium? Did they try to goof around or did they take it seriously?

How well do you understand the water cycle on a scale of one to five? One being “what is the water cycle?” and five being you feel confident you could teach it to another person.

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Have them draw the water cycle, labeling it with the vocabulary words transpiration, condensation and precipitation. The Water Cycle in a Terrarium

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Differentiation

Calling on students with their hands up during the opening discussion piece instead of using equity sticks relieves the pressure of students who may not know the answer right away.

Having students make the terrariums in groups instead of individually could save on cost. They can also help each other to create the terrarium.

Using and sharing a schedule helps students have clear boundaries and expectations as well as know what is happening next.

Remediation

Extension/Enrichment

The students create terrariums in a group and compare using water versus gatorade in the terrarium. Or compare trying to grow the terrarium in direct sunlight versus darkness.

You could add bugs to the terrariums.

You could create an extra large terrarium in a 20 plus gallon tank.

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