Class 4: What’s Stomata With You?

 

One liner about the lesson:

Quick Snapshot:

Objectives 

By the end of the class, students should be able to:

 

NGS Curricular Standards:

• MS-LS1-2 From Molecules to Organisms – Structures and Processes

ASPB Guidelines

• Molecules to Organisms – Photosynthesis: During photosynthesis, plants convert energy from sunlight to produce sugars from carbon dioxide. These sugars provide both energy and the carbon skeleton to build more complex molecules required for growth. Photosynthesis provides the biosphere with food, energy, and oxygen.

Materials 

Art

• Multi-Colored Markers
• Clay (Back-Up Art Activity)
• Clear Nail Polish
• Clear Tape
• Microscope Slides
• Compound Light Microscopes
• Leaves (for Stomatal Peels)

Movement (Lecture)

• Laminated cards labeled: Carbon Dioxide, Water, Sunlight, Arrow, Sugar, Oxygen
• Tape to mark spots on the floor

Microscope (Lecture and Art)

• 6 microscopes arranged around the room
• Pre-prepared stomata peels from a variety of leaf types (each slide clearly labeled with the plant name and habitat type)
• A whole leaf sample placed beside each microscope, so students can see the leaf the peel came from
  • Leaf types may include: Succulents, Temperate species, Variegated leaves, Tropical species

Preparation(s)

Movement activity

Steps:

1. Mark out spaces on the floor for students to stand.
2. Hand out laminated sheets — each student becomes part of the equation.
3. Have students arrange themselves in order:
   
   
   
   Carbon Dioxide + Water + Sunlight → Sugar + Oxygen
4. Discuss what’s happening at each step.
5. Emphasize: This entire process happens inside the leaf

Microscope activity

• Start with a demonstration of a stomata peel so students can see the process.
• Divide students into groups evenly among the microscopes. 
• Give them a few minutes to look through the microscopes and practice focusing. 
• Ask them to describe what they see. 

Art Activity 

Blind Contour Drawing 

• Students will rotate through the microscopes.
• At each station, they have two minutes to make a blind contour drawing of what they see. They will only look through the microscope the whole time, not at their page!
• Encourage students not to worry about the perfection of the drawing, but rather to pay attention to the process. This is about observation, not their fine art skills!

BACK UP: Clay Modeling 

• If time allows, students can sculpt a 3D model of stomata out of clay.

Class summary

Class began with another round of introductions; students shared their names, and pronouns if comfortable. Instructors reminded students that their engagement would be rewarded with a sticker. Then, in place of an icebreaker question, instructors took ~5 minutes to conduct a “check your knowledge” session, reviewing content from the previous lesson. Students were given multiple choice cards (A,B,C and D) to hold up in order to answer multiple choice questions about stormwater runoff and combined sewer overflow (seen at beginning of slideshow).

The next 20 minutes were spent on new content, explaining photosynthesis and its importance, using both lecture slides, and movement activity. Students were given laminated sheets with different parts of the photosynthesis equation, and were directed to stand on marked spaces on the floor to offer a large scale visualization. Then, each step of the process was explained, with emphasis on the fact that the entirety of the process happens inside a single leaf! Next, instructors introduced the structure and function of the stomata, including its subtle differences across environments.

The lecture ended with a hands on, microscope activity, where students were able to look through several scopes arranged throughout the classroom, showing stomatal peels from real leaves!

The next ~25 minutes were spent on an art activity, where students made “blind contour drawings” of the stomata as they observed them through the microscopes.

Lecture slides 

Art 

Below are images of student work. Blind contour is a technique that does not emphasize photorealism or “perfection,” but allows the artist to engage deeply with what they observe. Technique involves the artist not taking their eyes off the subject they seek to depict, as well as lifting their drawing implement off the page as little as possible.

 

[insert student work here]

Assessment/reflections 

• What was your favorite plant to look at under the microscope?
• What did you notice about texture and observation of stomata when doing the blind contour drawing
• How was using the microscopes? What was it like to look into an unknown world tinier than ourselves?

Learning outcomes 

• Students will be able to explain the role of stomata and how they help plants exchange gases and release water.
• Students will identify the inputs and outputs of photosynthesis and understand that this process happens inside leaves.
• Students will use a compound microscope to observe and describe stomata from different types of leaves.
  
  
• Students will compare how leaves from different environments differ in stomata density or size and connect these differences to plant adaptations.
• Students will practice close observation through blind contour drawing to translate microscopic details into visual form.

Instructor notes