How Deep Can You Go?

The Levels of The Ocean

BEFORE READING

OBJECTIVES:

• After receiving instruction from the teacher, TSWBAT complete the KWL chart with at least five items listed for each column.
• After receiving instruction from the teacher, TWBAT complete the GIST worksheet with a partner with one 20-word sentence per section in the text.
• After discussing Venn diagrams, TSWBAT complete a Venn diagram comparing and contrasting the three different oceanic life levels.
• After reading the text, TSWBAT name three specific characteristics of each oceanic life level.

I. Motivation

Teacher:   "Life appeared in the ocean about 3.8 billion years ago.   Its first inhabitants were neither animals nor plants, but microscopic creature called bacteria.   Over time, some bacteria used the Sun's energy to make oxygen, the gas that allows plants and animals to survive.   Once there was oxygen, life the ocean was changed forever.   Sponges, jellyfish, worms, and starfish appeared in turn.   Fishes followed millions of years later.   Some of these fishes' descendants developed lungs and legs.   They learned to breathe and to move around on land.   They grew into amphibians such as frogs.   They were followed by reptiles, birds, and mammals (like us!).   Even though a large number of animals today live on the land, the ocean is still home to most creatures.   In fact, 80 percent of the animals on Earth live in the water!   The principal marine groups are sponges, cnidarians ( n?-dâr'?- ? n) , worms, mollusks, echinoderms, crustaceans, fishes, reptiles, and mammals" (Fortin, 2004, 46).  

"Where these animals live within the ocean depends on a variety of factors.   One of the factors affecting this is the temperature of the ocean water.   Temperature in the ocean varies mostly on the amount of sunlight which can penetrate and warm the water.   Today we will learn about the different levels of the ocean and the types of creatures and plants that make their habitat in each of them."

II. Prior Knowledge

Note: The following provide information to tap into students' prior knowledge.   As not all schools' curriculum is the same, use what is relevant to your own curriculum to help students connect what they are learning to what they have learned in past.  

A. Number the students off into three groups.   Assign each group either as mammals, reptiles, or fishes.   "In your groups I want you to come up with the key characteristics of the type of animal I assigned you.   You will report back to the group your findings." The following are definitions of each type of animal.

Mammal:   A class of vertebrates characterized by the production of milk by the females and in most cases, by a hairy body covering.   Most mammals give live birth to their young.   Human beings are mammals.

Reptiles:   A class of scaly vertebrates that usually reproduce by laying eggs.   Lizards, snakes, turtles, and alligators are reptiles.   Reptiles are cold-blooded animals

Fish:   Any of various cold-blooded, aquatic vertebrates, having gills, commonly fins, and typically an elongated body covered with scales.

B. "Can someone name and point out on a map one of the world's oceans for me?"   Students should recognize the Atlantic, Pacific, Arctic, Indian, and Southern Oceans.

C. "Let's review the Water Cycle.   What happens first?"   Heat from the sun causes water to evaporate from the ocean and become water vapor.   "Next?"   The water vapor forms clouds.   "And what do the clouds do?"   They produce rain that falls to the earth.   "What happens to that rain?"   It goes back to the ocean through rivers and underground streams.  

D. "What are the names for some of the different landforms that can be found under the ocean?"   Continental slope, submarine canyon, guyot, oceanic ridge, oceanic trench, island arc, seamount, abyssal plain, continental shelf, volcano, undersea mountains.

III. Purpose

Teacher:  "Today we will be extending what we have already learned in our Oceans unit even further so that you all may gain a greater appreciation for the value of our oceans.   Our purpose for today's lesson is to learn about the different levels of the ocean in relation to the temperature and sea life at those levels.   We are going to read a section in our science books, Exploring Earth Science, along with various other texts that will help increase our understanding of this subject.   Throughout our reading, we will be thinking critically about why certain types and amounts of sea life can only be sustained at specific ocean depths."

IV. Strategy Instruction

Teacher:  "To help us comprehend the texts that we will be reading, each of you will be filling out a KWL chart ."    Hand out the KWL worksheet to the students (click on the link for one you may print off and use).   "We have used this reading strategy in the past so let's review."     

1. "The K stands for 'what you know or think you know.'   In this column you think about what you think you know or know you know about the topic you are reading about.   In this column one should list as many things as possible as one knows in statements."

2. "The W stands for 'what you want to know.'   In this column you list the things you would like to learn about the topic.   You may write statements or questions.   Even if there is something that just interests you a little bit, write it down!"

3. "The L stands for 'what you learned.'   At the end of the lesson we will finish the worksheet by filling in this column.   Here you will write the things that stuck out to you, were new to you, or you felt were important to remember."

Model:

Note:   It might be helpful to run a copy of the KWL chart provided not only as a worksheet for the students, but also as an overhead so that one can watch the teacher use it during while modeling.   One could also create the chart on a chalkboard or whiteboard if an overhead projector is unavailable.

Teacher:   "So that each of you has an idea of what I expect from you in your KWL charts, I will write a few sample statements in the K & W columns.   I will model the L column after we have finished reading."

"First, I will think about what I already know about the temperature and sea life at the different levels of the ocean.   I know that as water gets deeper it usually gets colder.   Therefore, under the K column, I am going to write, 'Water is usually colder at the bottom than at the top.'   I would continue to list the things that I know in bullets like I have the first item."

"Secondly, I would brainstorm about what I want to know about ocean life at different levels in the ocean.   One question I have is whether all animals can swim to the bottom of the ocean.   So under the W column I will write, 'Can all animals swim to the bottom of the ocean?'   Then I would continue to list the rest of the questions I have."

Guided Practice:

Teacher:   "Now that I have demonstrated how to complete the KWL chart, let's do a couple of statements together.   Do I have a volunteer to share something they already know about the levels of the ocean?"   When a student shares, write down what they said in the K column.   Ask for another volunteer to share something they know.   "Now, what would you like to know about the levels of the ocean?"   Have two people share their questions and write them under the W column.

DURING READING

V. Text Structure

Exploring Earth Science , p. 213-214, 223-228

Teacher:  "The text that we are going to read is expository.   It uses description and details to present information about the temperature of the ocean and the various forms of life at different levels of the ocean to the reader.   The text is also sequential because it tells us about one level of the ocean after another.   This will be helpful to you when reading through the text."

"A reading strategy that can be helpful in comprehending expository texts is the GIST strategy.   You will be using this strategy with a partner as you read through the text."

GIST STRATEGY PRESENTATION - Link to a description of the strategy and how it is executed

GIST WORKSHEET - Link to the worksheet the students can use while reading the text

VI. Vocabulary

Note: The following is a list of the new vocabulary words that will be present in this section of the text.   Different teachers have different ways of approaching vocabulary instruction; you may want to create a word wall where your vocabulary words will go or type up a vocabulary sheet for your students.   Regardless of how you choose to go about it, it is wise to address the new vocabulary words and go over them with your class to ensure better comprehension.

1. Surface Zone (p.213) - the zone where the water is mixed by waves and currents
2. Thermocline (p.213) - zone of rapid temperature change
3. Deep Zone (p.213) - area of extremely cold water
4. Plankton (p.223) - the largest group of animals and plants in the water, float near the surface where sunlight penetrates the water
5. Nekton (p.223) - forms of ocean life that swim
6. Benthos (p.224) - organisms that live on the ocean floor, may be plants or animals
7. Intertidal Zone (p.225) - the region between the low and high tide lines
8. Neritic Zone (p.227) - extends from the low tide line to the edge of the continental shelf
9. Open-Ocean Zones (p.228) - there are 2 open ocean zones, the bathyal zone and the abyssal zone
10. Bathyal Zone (p.228) - begins at the continental slope and extends down about 2000 meters
11. Abyssal Zone (p.228) - begins at about 2000 meters and extends to an average depth of about 6000 meters

VII. Content

The following link will take you to the national standards for science in grades 5-8.   The information that students should have previously mastered can be located on the same link through the K-4 national standards.

http://www.education-world.com/standards/national/science/5_8.shtml

AFTER READING

VIII. Questioning

The questioning method used is the QAR (Question, Answer, Relationship) strategy.   Students are not only expected to give the answer to the questions, but also tell how and where they found their answers.

1. "What is the major source of heat for the ocean?"   (Right There)   The sun.
2. "What do you think happens to the water temperatures at the Caribbean Sea and off the coast of England during winter?"   (Author and Me)   The temperatures decrease.
3. "What are the factors that affect the plant and animal life in the ocean?"   (Think and Search)   The amount of sunlight that penetrates the ocean, the temperature of the water, and water pressure.
4. "Name some plants and animals that live in the intertidal zone and state why they are able to survive there."   (Think and Search)   Crabs live there because they can bury themselves in the sand when the tide is low.   Worms live there because they can burrow down into the wet sand when the tide is low.   Sea Urchins can close themselves up to survive without water for short periods of time.
5. "What do you think would happen if plants and animals that are supposed to live in the intertidal zone were placed in the open-ocean zone?"   (On My Own)   Answers may vary.

IX. Strategy Instruction

Teacher:  "Let's finish up our KWL charts now.   Please pull them back out.   Let's go over some of the things you wanted to learn.   Were any of your questions answered?"   Take responses from various children.   "Good.   Well, before we get ahead of ourselves, let's see if my question was answered."

Model:

Teacher:  "My question was 'Can all animals swim on the bottom of the ocean?'.   Well, after reading the sections of the book I now know that no, not all animals can swim at the bottom of the ocean.   I do know now that only small animals can live at the bottom of the ocean where there is no light and the water pressure is very great.   So, under my L column I am going to write 'Only animals who are very small and can withstand the very harsh conditions of the abyssal zone can swim at the bottom of the ocean.'"

Guided Practice:

Teacher:  "Please share with me one of your questions that was answered."   Allow for students to respond.   "What would you write in you L column to display what you learned?"   Students again respond and discuss possible answers.   "Great!   Now go ahead and finish filling out your KWL charts."

X. Writing to Learn Activity

Note: Writing to learn activities may expand over more than one day because this lesson is only one of a whole unit on Oceans.   The following is only my suggestion for this day's lesson.   Others may find it beneficial to change this activity, however, to meet the specific needs of the children in their own classrooms.

Pass out the Venn Diagram worksheet (click on the link for one you may print off and use) to the students.   Split the students into groups of three.   Teacher:  "Each of these large circles represents one of the Ocean Life Zones.   Please label each circle as one of these zones--either the intertidal, neritic, or open-ocean zone--on the line cutting through each circle.   In the areas where the circles do not overlap you will be writing characteristics about that zone.   Where the circle overlaps with the neighboring circle, write things that the two zones have in common.   In the middle, you will write characteristics that all three zones share.   Does anyone have any questions?"   Answer questions as needed.   "Alright, you may begin!"

XI. Closure

Teacher:  "If you have not finished the Venn diagram worksheet, please take it with you today and finish it up before class tomorrow."

"Our purpose for today was to learn about the different Ocean Life Zones and figure out what the relationship was between the sea life that lived in these zones and the temperature of the water.   What relationships or conclusions have you drawn about this through our inquiries today?"   Allow for student discussion facilitated by the teacher.

"Tomorrow we will be taking a more in-depth look into the different creatures that roam the ocean.   We will be categorizing them according to what Ocean Life Zone you think they belong in.   Come prepared tomorrow to class with the name of one ocean animal or plant and what zone it can be found in."

XII. References & Other Helpful Resources

Fish. (n.d.). Dictionary.com Unabridged (v 1.1). Retrieved April 01, 2007, from Dictionary.com website: http://dictionary.reference.com/browse/fish

Fortin, C (2004). Scholastic atlas of oceans . New York, NY: Scholastic Inc.

Mammals. (n.d.). The American Heritage New Dictionary of Cultural Literacy, Third Edition.   Retrieved April 01, 2007, from Dictionary.com website: http://dictionary.reference.com/browse/mammals

Maton, A, Hopkins, J, Johnson, S, & LaHart, D (1995). Exploring Earth science . Englewood Cliffs, New Jersey: Prentice Hall.

Pratt, K. (1994). A swim through the sea . Nevada City, CA: DAWN Publications.

Reptiles. (n.d.). The American Heritage New Dictionary of Cultural Literacy, Third Edition.   Retrieved April 01, 2007, from Dictionary.com website:  http://dictionary.reference.com/browse/reptiles

Waters, J. (1994). Deep-sea vents: Living worlds without sun . New York, NY: Cobblehill Books.