Class 5: Tiny Worlds + Small Cities – How Green Spaces Cool Big Cities

Objectives 

At the end of the lesson, students should have an understanding of how

• Plants have the capacity to change the temperature and water in an ecosystem
• This can be observed both on a small scale (terrariums, which model an enclosed ecosystem), and on a larger scale (entire neighborhoods and cities).

NGS curricular standards: 

MS-LS2-1 Ecosystems: Interactions, Energy, and Dynamics: Students can analyze and interpret data to provide evidence for the effects of resource availability on organisms and populations of organisms in an ecosystem. 

ASPB Principles: 

• Ecosystems – Biogeochemical Cycles – Plants, as primary producers, play an essential role in the nutrient cycling through the biosphere.
• Ecosystems – Biodiversity – Plants are key to maintaining complex natural systems. High biodiversity ensures greater ecological resilience in the face of ecological changes. Human activities can impact biodiversity which can further impact ecosystem health and associated ecosystem services.
• Evolution – Environmental Response – Plants live in and have adapted to a wide variety of environments. Many plants have also co-evolved with microbes and animals.

Materials: 

• Feeling Cards 
• HOT and COOL Signs 
• Tape
• Jars w/ Closed Lid
• Sharpies
• Decorative Gravel
• Activated Charcoal 
• Peat Moss
• Plants
• Figurines
• Spray Bottles
• Potting Mix
• Plastic Spoons

Preparation: 

• Tape the emoji cards up around the room for “vibe check”
• Tape the hot and cold signs on opposite sides of the room 
• Set-up terrarium supplies in containers with spoons (supplies will be distributed one at a time, at each step of the process). Each student will begin with just a jar!

How to make the terrarium: 

1. Write your name on your jar lid so you know which one is yours.
2. Add a 1–2 inch layer of gravel at the bottom.
3.  Add ¼–½ inch layer of activated charcoal over the gravel. Make sure it fully covers the stones.
4.  Spread a layer of peat moss over the charcoal, fully covering it.
5.  Add about 1 inch of potting mix on top of the moss. Sprinkle evenly and gently press down. The base layer should take up about one-quarter to one-third of the jar to leave room for plants.
6. Decide how you want to arrange your plants before digging small holes in the soil. Use fingers or a spoon to create holes, place roots carefully, and gently press soil around them.
7. Add small figurines or decorative elements if desired.

Class summary 

Class began with a 5 minute round of names and (optional) pronouns, as well as a quick “feelings” check in, where students were directed to stand near emoji cards displaying around the classroom that most matched how they were feeling at that moment.

Because this class marks the halfway point in the Girls Inc., PLACE Lab collaboration, students were asked to fill out a mid-program survey, offering a space for them to share thoughts, impressions and feedback for instructors.

This lesson, students were introduced to a new system for rewarding participation/engagement in the lesson – a raffle system, where participation was rewarded with a “ticket,” and numbers of tickets corresponded to a different thing – ie: 5 tickets = 1 sticker, etc. Instructors can be creative with this system, if choosing to replicate.

The icebreaker this class was a game of “hot or cool,” where students were shown images of different outdoor environments (in the lecture slides), and asked to describe whether each was hot or cool. This introduced the topic of urban heat island effect, and how trees are able to regulate temperature. An instructor used her own community as an example to explain the difference between concrete and no trees vs. public green-space, and introduced how access to shade/cool/trees is an equity issue. Students were encouraged to reflect on their own neighborhoods, and whether or not they experienced urban heat island effects. Icebreaker and slides should take ~20 minutes.

This topic was then further cemented for ~25 minutes with the art activity: making terrariums! Steps for this process are outlined under “Preparation.”

Class concluded as usual with a journal prompt, in the last ~5 minutes.

Lecture slides  

Student Artwork

Student terrariums, modeling enclosed ecosystems can be seen below!

[add artwork images]

Assessment/Reflections 

Journal prompts:

• What part of building your terrarium did you enjoy the most, and why?
• If you could change one thing in your terrarium to make it more like a real ecosystem, what would it be and why?

Learning outcomes 

• Explain the layers and components of a terrarium and their functions in maintaining a balanced ecosystem.
• Describe how plants regulate temperature, moisture, and the water cycle in small ecosystems and on Earth.
• Connect the greenhouse effect in a terrarium to the broader concept on Earth.
• Reflect on how human activity and plant coverage impact local temperatures and community environments.

Instructor notes