Lesson Title: Why Do Leaves Change Colors?

By: Michelle Blakley

Instructional Coach: Jenina Sorenson

Description: In this lesson students will explore the basic needs of plants and what will happen if one of its major organs were missing. Students will be read aloud to and given a chance to participate in hands on experiments. Students will use the leaves around their school to complete the experiment and also to keep track of the changes of the leaves over time. They will journal their observations as the leaves change colors and use the Kestrel to keep track of temperature, humidity, wind chill and heat index. This will help the students to possibly generate more questions as they are completing their observations.

Grade level(s) 3rd Grade

Essential questions: What affect would there be on a plant if one of its major organs were missing? Why do leaves change colors?

Student learner objective – connections to the GLE’s:Identify the major organs (roots, stems, flowers, leaves) and their functions in vascular plants (e.g., absorption, transport, and reproduction). (DO NOT assess the term vascular) (LO.1.D.a) (1.6; 1.8; 3.5) DOK 1

Demonstrate through words or pictorial illustrations the basic needs of plants and what would occur if one of those needs were not met. (LO.1.A.a) (1.2; 1.3; 1.6; 3.1) DOK 2

Describe the basic needs of most plants (i.e., air, water, light, nutrients, and temperature). (LO.1.A.a) (1.2; 1.3; 1.6; 3.1) DOK 1

Describe and explain the parts of a plant and how they help the plant survive. (LO.1.D.a) (1.6; 2.3; 3.5) DOK 2

Read and interpret information from line plots and graphs (bar, line, pictorial) (D1C3) (1.10) DOK 2 

Featured Scott Foresman’s textbook: Scott Foresman, 2006, TE pp. 4-29, 106, 150-151, 359-461 Scott Foresman Leveled Readers, TE Chapter 1:

o Plants and How They Grow , Plants and Trees Growing, Tree Life

Featured picture books: Why Do Leaves Change Colors ? By Besty Maestro (Non-fiction) Leaf Problem by Jonathan Emmett (fiction)

Time needed:15 days (or enough days for students to record changes in the leaves)

Academic vocabulary words (with definitions)

Sun—as primary source of light and food energy

Roots – Parts of a plant that hold the plant in place and that take in water and nutrients from the soil. The roots of the old oak tree are deep inside the ground. (The roots of a plant soak up vitamins and minerals. They also store food for the plant). Leaves – Parts of a plant that use sunlight, air, nutrients, and water to make food for the plant. The leaves on the plant are long and thin.(The leaves make food (sugar) for the plant. They also take in carbon dioxide and release oxygen into the air).

Stem – Parts of a plant that holds it up and that carries water and nutrients to the leaves. The stem is long and green. (The stem supports the plant. It has many thin tubes that carry water, minerals, and food through the plant).

Flower – The part of a plant that makes seeds. Some plants have many flowers. (A flower is the part of a plant that makes seeds).

Fruit - Some plants have fruits. Fruits protect and hold the seeds of the plant. Many animals eat fruits, which can help the seeds spread to different areas.

Chlorophyll – Green material in plants that captures energy from sunlight for photosynthesis. (Chlorophyll is a green pigment that is found in plants leaves. It helps the plant make food).

Photosynthesis – The process in which plants make their own food. (Photosynthesis is the process that plants use to make food. During photosynthesis, the plant turns sunlight, chlorophyll, and carbon dioxide into food (sugar) and oxygen).

Sugar - Sugar is the type of food that plants make in their leaves. Sugar is also called glucose.

Oxygen - Oxygen is a type of gas (air) given off during photosynthesis. People and animals need oxygen to breathe.

Carbon Dioxide - A type of gas (air) needed by plants for photosynthesis. Plants use up carbon dioxide and produce oxygen. People and animals create much of the carbon dioxide that plants need to stay alive.

Depth of knowledge level:1-3 addressed throughout the lesson (see student learner objectives)

Materials needed:KestrelScience JournalParking Lot QuestionsChart PaperBudburst JournalPencilLeaf Trouble/Why Do Leaves Change Colors? /Scott Foresman TextbookLeavesSmall Jar (a baby food jar works well)Cover for Jars or Aluminum Foil or Plastic WrapRubbing AlcoholPaper Coffee FilterShallow PanHot Tap WaterPlastic Knife or SpoonSticky Notes

Lesson narrative:(Before Teaching This Lesson)Students will be taught on how to use the Kestrel. Prior to the lesson the students will have already been using the recording sheet and understand its purpose to measure and compare weather and temperature changes from day to day, week to week, month to month. The students will also note the changes with the leaves on the trees outside of the school. The students will keep track of this data to share on line.Students will understand the use of the Parking Lot. Students will understand that scientists are always asking questions, seeking new information, and the more they learn the more questions they have.

Engage: In this part of the lesson the students will be introduced to a story entitled Leaf Trouble. The students will be asked questions before during and after reading that will cause them to use the questioning, inferring and synthesizing reading strategies. The students will try to make predictions about what causes the problem with the leaves.

Engage/Formal Assessment (OWL Chart, Science Journal and Parking Lot Questions):Day 1: The students will go outside and collect 2-3 large leaves from the same tree. They will bring the leaves inside and use a magnifying glass to observe the leaves. As

they observe the leaves they will fill out the (O) and (W) part of the OWL Chart. The students will also be able to add questions to the parking lot. The students will then come together to share their responses for the class OWL chart. The (O) portion of the OWL chart allows students to record what they observe encourage students to use their senses. The (W) is where students write their “I wonders”……… Students should continue to develop their wonderings as they continue to learn new information. The final part of the chart is the (L) this will not be filled in until the end of the unit where the students will explain what they have learned.

Day 2: The next day the teacher will read the story Leaf Trouble by Jonathan Emmett. The student will be listening to see why the leaves are having trouble and if the squirrel is able to help them. The teacher will ask the students questions throughout the story to guide them into making inferences and synthesizing the read aloud.

Explore/Informal Assessment (Science Journal) Day 3: The students will prepare to complete this experiment and record the results in their science journals. The assigned students will first go outside and use the Kestrel for data to be recorded. The students will continue using the Kestrel weekly and observing the leaves outside after this experiment is completed. Have the students come up with a hypothesis: a statement such as it is predicted that... and record what they see before, during and after the experiment in their science journals. (Experiment was taken from http://www.education.com/activity/article/Leaves_Change_fifth/)

What You Will Do The students will be given 2-3 large leaves from the same tree type. The students should tear or chop the leaves into very small pieces and put

them into the small jar(s). Add enough rubbing alcohol to the jar(s) to cover the leaves. Using a plastic knife or spoon, carefully chop and grind the leaves in the

alcohol. SAFETY NOTE: rubbing alcohol can be harmful if mishandled or misused. Use in a well-ventilated area, and avoid contact with skin.

Have the students cover the jar(s) very loosely with a lid, plastic wrap or aluminum foil. Place the jar carefully into a shallow tray containing 1 inch of hot tap water.

Keep the jar(s) in the water for at least a half-hour, longer if needed, until the alcohol has become colored (the darker the better). Twirl the jar gently about every five minutes. Replace the hot water if it cools off.

Have the students cut a long thin strip of coffee filter paper. Remove the jar(s) from the water and uncovered. Have the students place

the strip of filter paper into the jar(s) so that one end is in the alcohol. Bend the other end over the top of the jar and secure it with tape.

The alcohol will travel up the paper, bringing the colors with it. After 30-90 minutes the colors will travel different distances up the filter

paper as the alcohol evaporates. The student should be able to see different shades of green, and possibly

some yellow, orange or red, depending on the type of leaf.

* The students will complete an Anticipation Guide about leaves. (See the attached Anticipation Guide)

Explain/Exit Ticket:Day 4: The teacher will read Why Do Leaves Change Color? by Besty Maestro aloud. The students will need to listen to see why leaves change colors. The students will be given an opportunity to write on their think pad as the story is being read to see if they are able to tell why leaves turn colors. The students will then need to complete an Exit Ticket about the changing colors of leaves. (See the attached Exit Ticket)

Elaborate/Extend (Project Budburst)Day 5:

The students can collect leaves from different trees other than the ones that they used and repeat the same steps to the experiment. In a learning lab as the teacher meets with small groups at the teaching table.

Students can set up another learning lab where they plant seeds and change one of its basic needs. For example: the students can water one with water and another one with sprite. The students will be testing, observing, and recording data to see if removing one of a plants basic needs (water) will it still survive.

Students will still continue to monitor the leaves and record their data so it can be uploaded to Project Budburst. Students can use their science journals, or use the journal pages found at http://neoninc.org/budburst/buddies/journal_pages.php to record their collected data.

Evaluate/Summative Evaluation:Day 6: A summative assessment is attached in a PDF (Why Do Leaves Change Color?). The assessment will help the teacher summarize the development of the learners at the end of the lesson. The teacher will use the data from the summative assessment to develop further lessons to re-teach those students in small group/workstations who are stilling having difficulties/misconceptions with understanding why leaves change colors.

Misconceptions(Misconception list found at www.nsdl.org)

Plant PartsWhile most students recognize the stem, leaves, and flowers of plants, fewer identify roots as a common structure. Students may need more experiences observing root systems of various plants.

Students may think... Instead of thinking...

Plants take in all substances they need to grow through their roots.

Plants take in air through their leaves. Chloroplasts in the plant absorb the sun's energy for use in photosynthesis. Water

and minerals are taken in through the roots.

Leaves take in water. Water is taken in through the roots.

Plants get their energy from the soil through roots.

Chloroplasts in the plant absorb the sun's energy for use in photosynthesis. Water and minerals are taken in through the roots.

Photosynthesis and RespirationAgain, the tendency to give plants human or animal characteristics leads to misconceptions. For example, students often believe that plants perform "reverse breathing" in which they inhale carbon dioxide and exhale oxygen. In reality, plants use and produce both carbon dioxide and oxygen through two processes: photosynthesis and respiration.

Photosynthesis is the process by which plants convert carbon dioxide and water into sugar and oxygen. Photosynthesis requires energy, and a plant's chloroplasts absorb solar energy to fuel these reactions. Photosynthesis can only happen during the day when sunlight is available.

Respiration , on the other hand, is the breaking down of sugars (and oxygen) to provide energy for plant growth. Respiration also produces carbon dioxide and water, essentially the opposite of photosynthesis. Respiration does not require light and can happen at night.

Plants do release oxygen into the atmosphere, as they produce more than they need during photosynthesis.

The word "respiration" is often used incorrectly to describe breathing, but the two processes are different. Breathing, which occurs in animals, is the process of obtaining oxygen and removing carbon dioxide via lungs or gills. Respiration, as previously described, is the release of energy from food and occurs in both animals and plants.

Students may think... Instead of thinking...

Plants breathe by inhaling carbon dioxide and exhaling oxygen.

Plants take in air through their leaves. Both carbon dioxide and oxygen are used for different processes. Photosynthesis requires carbon dioxide, while respiration requires oxygen. While plants do release oxygen, it is a by-product of photosynthesis and is not released through breathing. Plants do not breathe. They absorb air through the stomata (pores) in their leaves.

Plants obtain their energy directly from the sun.

Energy from the sun allows the plant to carry out photosynthesis and produce sugars. Respiration breaks down these products and provides energy for

the plant.

Sunlight helps plants grow by keeping them warm.

Chloroplasts in the plant absorb the sun's energy for use in photosynthesis.

Safety: The students will be given small amounts of alcohol to use in the experiment.

How to use the alcohol will need to be addressed and students will need to be monitored.

Allergies certain students might have to various plants and leaves should be noted

Boundaries of where the students can find/look for their leaves should be explicitly explained

Reading comprehensive strategies: Leaf Trouble by Jonathan Emmett

Questioning Determining Importance Inferring

Why Do Leaves Change Color? By Betsy Maestro/ Scott Foresman Textbook Determining Importance

General suggestions for students and teachers: It will take a while for the leaves to change colors in the experiment. If possible start the experiment towards the beginning of the day and allow the student’s time to record their observations and check hypothesis throughout the day.

Bibliography:

http://www.netplaces.com/kids-science-experiments/biology/try-this-falling-leaves.htmibliography:

http://www.associatedcontent.com/article/5789380/_fall_science_lesson_why_do_leaves.html?cat=4

http://www.education.com/activity/article/Leaves_Change_fifth/

http://homeschooling.about.com/library/sciexperiment.pdf

http://teachersnetwork.org/readysettech/leaves.htm

Ecurriculum-Hickman Mills School District curriculum website for teachers

www.nsdl.org-misconception list

http://neoninc.org/budburst-Project Budburst

Student Work Pages and Answer Keys are Attached

Assessment is on a separate PDF file.

O -observe W-wonder L –learned

Name: ______________________________________________

Date: ______________________________________________

Class: ______________________________________________

Let’s Learn About Leaves Anticipation Guide

(Questions taken from http://teachersnetwork.org/readysettech/leaves.htm)

Before Reading True or False After

Reading

____1. Without chlorophyll, a plant would

still be able to make the food that it needs? ____

____ 2. When summer ends and fall begins, the days get shorter and shorter? ____

____3. The leaves changing colors in

autumn show us that a tree is speeding up its food factory for the winter?

____

____4. Chloroplasts are special parts of a

plant’s cells. This is where you find chlorophyll. ____

____ 5. Chlorophyll is what makes plants green in color? ____

Exit Ticket Name: _______________________________________________________________________ Illustrate,

Describe, and Explain in your own words why leaves change colors

Answers (1) F, ( 2) T, ( 3) F, (4) T , (5) T

Exit Ticket Name: _______________________________________________________________________ Illustrate,

Describe, and Explain in your own words why leaves change colors

Answer to Exit Ticket (Students should be able to identify that leaves change color because the green chlorophyll disappears from the leaves as the days get shorter).

Kestrel Reading________________________________________________________

0 1 2 3 4 5 6 7 8 9 10 11 12+

Calm Light air

Light breeze

Gentle Breeze

Moderate Breeze

Fresh Breeze

Strong Breeze

Near Gale Gale Strong

Gale Storm Violent Storm Hurricane

Wind Speed

Max Gust

Max

Avg. Speed

Avg

Temperature Wind

Chill

Humidity

Heat Index

Dew Point

Week 1

Week 2

Week 3

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