Why Do Leaves Change Colors? Script

Warm-Up: What Do You Notice? (5 minutes)

"Good morning, everyone! Let's start by thinking about what's happening outside right now. As you look out the window, or when you walk to school, what do you notice about the trees and their leaves as the seasons begin to change? Has anyone seen a leaf that isn't green anymore? What colors have you noticed?"

(Listen to student responses. Guide them to observe the changing colors.)

Introduction: Why The Change? (5 minutes)

"That's right! Many of you have noticed those beautiful red, orange, and yellow leaves. It's one of the most stunning parts of autumn. But have you ever stopped to wonder why this happens? What's the science behind this amazing transformation? Today, we're going to become leaf detectives and uncover the mystery of why leaves change colors!"

(Display Why Do Leaves Change Colors? Slide Deck - Slide 1-2)

"Leaves are truly incredible! They're like tiny food factories for the tree. All summer long, they work hard using sunlight, water, and air to make food for the tree to grow. This important process is called photosynthesis."

The Science of Color (15 minutes)

(Display Why Do Leaves Change Colors? Slide Deck - Slide 3)

"During the spring and summer, the leaves are full of a special green ingredient called chlorophyll. Chlorophyll is amazing because it's what captures all that sunlight to help the tree make its food. It's so powerful that it gives the leaves their bright green color, masking any other colors that might be present."

(Display Why Do Leaves Change Colors? Slide Deck - Slide 4)

"But what happens when autumn arrives? The days get shorter, and the air gets cooler. Just like we get ready for winter by putting on warmer clothes, trees also start to prepare. They know winter is coming, and there won't be as much sunlight for making food.

So, the tree starts to break down the chlorophyll in its leaves. It's almost like the green curtain is slowly being pulled away, revealing what's been hiding underneath!"

(Display Why Do Leaves Change Colors? Slide Deck - Slide 5)

"As the green chlorophyll disappears, other colors that were in the leaf all along finally get a chance to shine! These are called carotenoids, and they are responsible for the beautiful yellow and orange colors you see. Think of carrots or corn – they get their colors from carotenoids!"

(Display Why Do Leaves Change Colors? Slide Deck - Slide 6)

"But what about those fiery reds and deep purples? Those colors come from another group of pigments called anthocyanins. What's really cool about anthocyanins is that they are only made in the fall, not all year like the carotenoids. They are created in the leaves when there are sunny days and cool, crisp nights. The brighter the sun and the cooler the nights (but not freezing!), the more anthocyanins are made, leading to those brilliant reds!"

(Display Why Do Leaves Change Colors? Slide Deck - Slide 7)

"So, to get the most spectacular fall color show, you need a perfect recipe: plenty of sunny days to make anthocyanins, cool (but not freezing) temperatures, and just enough rain to keep the tree healthy. Every year is a little different, which is why the fall colors can vary so much!"

Autumn Leaf Observation Activity (15 minutes)

"Now it's your turn to be scientists! I'm going to give each of you a few autumn leaves and a worksheet. Your task is to observe your leaves very carefully. Look at all the different colors you see. Think about what we just learned about chlorophyll, carotenoids, and anthocyanins. Can you identify which pigments might be making the colors in your leaves?"

(Distribute the collected leaves and Autumn Leaf Observation Worksheet. Circulate around the room, guiding students and encouraging discussion.)

"As you work, feel free to share your observations with a partner. What's surprising you about your leaves?"

Discussion & Review (10 minutes)

"Okay, everyone, let's bring our attention back together. What did you notice during your observations? Did anyone find a leaf with all three colors? Yellow and orange? Red and brown?"

(Facilitate a brief class discussion based on student observations and worksheet responses.)

"Fantastic observations! So, to recap, what's the main green pigment we talked about that makes food for the tree? (Chlorophyll) And what happens to it in the fall? (It breaks down). What colors do the carotenoids show us? (Yellow and orange). And which special pigments make the reds and purples in the fall? (Anthocyanins)."

(Display Why Do Leaves Change Colors? Slide Deck - Slide 8)

"You've all done a wonderful job understanding the science behind why leaves change colors! It's an amazing process that shows us how dynamic and beautiful nature can be."

Cool-Down: Reflecting on Fall Colors (5 minutes)

"To wrap up our lesson, I'd like you to think about one new thing you learned today, or one interesting fact about changing leaves that you found surprising. We'll quickly go around the room and share!"

(Distribute the Leaves Change Cool-Down and have students write down their thoughts. If time, allow a few students to share orally.)

"Excellent shares, everyone! Thank you for being such attentive and curious scientists today!"

Leaves Change Warm-Up: What Do You Notice?

Instructions: Take a moment to think about the trees and leaves you've seen recently, especially as the seasons change. Answer the questions below.

1. What colors do you typically see leaves turn in the autumn?
   
   
   
2. Have you ever wondered why leaves change colors? What are your initial thoughts?
   
   
   
   
   
   
3. Describe a particularly beautiful or interesting leaf you've seen recently. What made it stand out to you?
   
   
   
   
   
   

Leaves Change Cool-Down: Reflecting on Fall Colors

Instructions: Please answer the following questions to reflect on what you learned today.

1. What is one new thing you learned about why leaves change colors?
   
   
   
   
   
   
2. Name one of the pigments we discussed today and what color it helps create.
   
   
   
   
   
   
3. What conditions (sunlight, temperature) help create the most vibrant fall colors?
   
   
   
   
   
   

Autumn Leaf Observation Worksheet

Instructions: Carefully observe the autumn leaves provided. Use your eyes to notice all the different colors, patterns, and textures. Answer the questions below based on your observations and what you learned in class.

Leaf 1: __________________

1. What colors do you see in this leaf? (List all that apply)
   
   
   
2. Based on what we learned, which pigments do you think are most active in this leaf right now? Why?
   
   
   
   
   
   
3. Draw or describe any interesting patterns or features you notice on this leaf.
   
   
   
   
   
   
   
   
   
   
   

Leaf 2: __________________

1. What colors do you see in this leaf? (List all that apply)
   
   
   
2. Based on what we learned, which pigments do you think are most active in this leaf right now? Why?
   
   
   
   
   
   
3. Draw or describe any interesting patterns or features you notice on this leaf.
   
   
   
   
   
   
   
   
   
   
   

Leaf 3: __________________

1. What colors do you see in this leaf? (List all that apply)
   
   
   
2. Based on what we learned, which pigments do you think are most active in this leaf right now? Why?
   
   
   
   
   
   
3. Draw or describe any interesting patterns or features you notice on this leaf.
   
   
   
   
   
   
   
   
   
   
   

Reflection Questions

4. Which leaf did you find the most interesting? Why?
   
   
   
   
   
   
5. How does observing these leaves connect to what we learned about chlorophyll, carotenoids, and anthocyanins?