ALEX Lesson Plan

     

What Color are the Leaves?

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  This lesson provided by:  
Author:TracyAnn Reece
System: St Clair County
School: Springville Elementary School
The event this resource created for:GEMS
  General Lesson Information  
Lesson Plan ID: 23946

Title:

What Color are the Leaves?

Overview/Annotation:

Where do the brilliant colors of fall come from? Most leaves appear green. In the fall, leaves turn orange, yellow, and red. Most leaves aren't changing colors. The pigments are always present in the leaves. The green pigment overpowers the other colors during spring and summer. Using chromatography, students will be able to see the colors always present in a leaf, even if the only color they can see is green.
This lesson plan was created as a result of the Girls Engaged in Math and Science, GEMS Project funded by the Malone Family Foundation.

 Associated Standards and Objectives 
Content Standard(s):

Local/National Standards:

NATIONAL SCIENCE EDUCATION STANDARDS CONTENT STANDARD C: As a result of activities in grades K-4, all students should develop understanding of The characteristics of organisms Life cycles of organisms Organisms and environments

Primary Learning Objective(s):

Students will identify the many colors in leaves by making chromatography strips.

Additional Learning Objective(s):

Students will change their ideas about seasonal changes through guided scientific inquiry.

 Preparation Information 

Total Duration:

Greater than 120 Minutes

Materials and Resources:

Why Do Leaves Change Color? By Betsy Maestro
Autumn Across America by Seymour Simon
students' science journals (teacher-created)
variety of fall leaves
fresh spinach leaves and beet leaves
porcelain or stoneware coffee mugs
smooth, round rocks
spoons
fingernail polish remover (distributed by the teacher)
safety scissors
round coffee filters
Q-tips with an end cut off
measuring cup
rubbing (isopropyl) alcohol (distributed by the teacher)
clear plastic cups
tape
rulers
pencils
Rubric
safety goggles
latex gloves (check for any latex allergies your students may have)

Technology Resources Needed:

Internet connection

Background/Preparation:

Vocabulary:
pigments - Coloring matter in animals, plants, or paint.
chromatography - A method scientists use to separate materials that differ by color.
Prior to beginning our lesson, we posted on the board and discussed "Things Good Scientists Do." These included: Listen to directions
Never put things near our mouth or eyes
Write down observations (what we see)
Wait for the teacher's instructions before touching materials

  Procedures/Activities: 
1.)Engagement/Motivation Activity: Place some leaves up on the board. "Something has been happening to the trees outside. Has anyone else noticed?" Show students the photograph of fall leaves from Autumn Across America . Then pose the question, "What do you know about leaves?" (students describe on page 1 in their science journal). Place a large leaf-shaped paper on the board. Ask students to share with the class what they wrote in their journal about leaves; write down their insightful contributions on the large leaf. Then ask students, "What do you want to learn about leaves?" Hopefully, one student will suggest, "Why do leaves CHANGE color in the fall?" The teacher may direct students toward this question if none of the students comes up with it. Divide the class into small groups of about five students. Give each group one specific type of leaf. For example, one group observes spinach leaves, while another group works with beet leaves, another group could use red maple leaves, etc. Students talk about the leaves in their group and record their observations in their journals. Ask students to specifically answer and draw, "What colors are in the leaf?" (page 2 in their science journal, record/draw observations).

2.)Show students the bottle of acetone fingernail polish remover. Use the acetone to remove your nail polish (optional). Ask students, "Knowing that acetone removes my nail polish, how could we design an experiment to test our question?" Students discuss methods in their group. Have the students make predictions before testing (page 3 of science journal). If they suggest using the acetone directly on the leaf, have them write in their journal what might happen.
Have the students put on latex gloves. Give them a Q-tip dipped in the acetone and ask them to try to remove the color from a leaf. The students will try swabbing the outside of the leaf with the acetone. The students will discover that the color is not removed. However, if the leaf is torn the green color will appear on the cotton swab. Students should try another method. If the students don't come up with breaking the leaf, the teacher could suggest, "Is the color on the outside of the leaf or on the inside?"
Now, have the students put on their safety goggles and ask them to leave on their latex gloves. Instruct the students to break up the leaves and put the pieces into the mug. Using a smooth, round rock, students grind and squish the leaves into smaller pieces. Before adding the acetone, have students observe the clear color in the bottle. Walk around to each group and add a spoonful of fingernail polish remover to extract the pigment from the leaves. Students keep grinding the leaves with the stone until they see that the liquid has gained some color from the spinach. Let the liquid sit for 1-2 minutes.
Students use the safety scissors to cut the coffee filter into a 2" x 8" rectangle (you could have a parent do this ahead of time for you, or do this yourself if time is a factor). Students use a Q-tip to pick up a drop of the colored liquid from the leaf grinding. Students place the drop one inch from the end of the coffee filter rectangle. (Teachers can draw a pencil circle to assist students with placement.) Let it dry. Then the Q-tip is used again to add a few drops to the same spot. Students should let each drop dry before adding the next drop. The teacher puts ¼ cup of alcohol in the clear plastic cup. Students carefully put the end of the filter paper strip—the end with the drops of dried leaf extract on it—into the alcohol, but do not let the colored drop touch the alcohol. Teachers may use paper clips in order to secure strips to the side of the cup. The alcohol will travel up the filter paper, separating the different colors in the leaf. (This could take up to an hour, or let them sit overnight.)
In their science journals, students write out and draw the experiment steps (page 4).

3.)(Day 2) Once the color has stopped moving, remove the filter paper from the alcohol, let dry, and observe the different colors that were in the leaves (page 5 of the science journal - tape the chromatography strip and record observations).
Introduction: Groups select one or two people to present what they discovered about colors in the leaves and show their chromatography strip to the entire class.
Then read Why Do Leaves Change Color? by Betsy Maestro. Students summarize their findings and draw a picture in their science journals (page 6). As a class, discuss and record on the board, "What did we learn?" with students' ideas coming from what they recorded in their journals.

(Autumn Leaves Quick Flick)
This is a short cartoon about why leaves change colors. It also has a short quiz at the end to assess students' understanding.

4.)Application: Have each group of students find a tree near the school that still has green leaves on it. Based on what they've just learned about the pigments in the leaves, have them predict what colors will appear in the leaves. Student should record, in their journals, predictions and observations for their tree. Observations of pine trees could lead to more in-depth exploration of the difference between evergreen and deciduous trees. If a tree turned an unexpected color, have students share their results.


Attachments:
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  Assessment  

Assessment Strategies

Students will discuss in their science journals what they predicted, what they observed (draw pictures), and what they learned from their experiments, the book, and group discussions. The Rubric can be used to assess students' science journals.

Acceleration:

During stations, have students visit the Autumn Leaves Quick Flick and take the quiz.

Intervention:

Provide lower level text for students that may need it. Also, find time to introduce this concept in a small group setting to those students who may struggle before it is presented to the class.


View the Special Education resources for instructional guidance in providing modifications and adaptations for students with significant cognitive disabilities who qualify for the Alabama Alternate Assessment.