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Geologic Timeline Objectives

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Geologic Timeline Overview Students will build a timeline using both a physical and digital medium to better grasp geologic time that encompasses all the time that has passed since the formation of Earth. The timeline will include and describe the continuous order of events and environmental interactions that have shaped the planet. For purposes of study, analysis, and discussion, the geological timeline can be broken down into different periods based on major geological and astronomical events as reconstructed through scientific investigation. Grades and Subject Areas Earth Science – 9th through 10th Grade Objectives Students will: ● Understand the concept of geologic time scales including eons, eras, epochs, and periods. ● Recognize on a timeline some of the mass extinctions that have occurred in Earth’s history. ● Learn about geologic changes that have occurred in Earth’s history. I Can Statements ● I can comprehend the concept of geologic time through Earth’s history. ● I can build a geologic timeline and explain the differences between eons, eras, epochs, and periods. ● I can show on my timeline some of Earth’s mass extinctions. ● I can explain the general geologic changes that have occurred in Earth’s history. 1 - Created by David Brannan – January, 2012 Curriculum Connections Alaska Content Standards Science C. Concepts of Life Science A student should understand and be able to apply the concepts, models, theories, facts, evidence, systems, and processes of life science: 1) develop an understanding of how science explains changes in life forms over time, including genetics, heredity, the process of natural selection, and biological evolution; D. Concepts of Earth Science A student should understand and be able to apply the concepts, processes, theories, models, evidence, and systems of earth and space sciences. 4) develop and understanding of the theories regarding the origin and evolution of the universe. Technology Content Standards D. A student should be able to use technology to explore ideas, solve problems, and derive meaning. A student should: 3) create new knowledge by evaluating, combining, or extending information using multiple technologies. ISTE Student Standards 1. Creativity and Innovation Students demonstrate creative thinking, construct knowledge, and develop innovative products and processes using technology. Students: c. Use models and simulations to explore complex systems and issues ISTE Teacher Standards 1. Facilitate and Inspire Student Learning and Creativity Teachers use their knowledge of subject matter, teaching and learning, and technology to facilitate experiences that advance student learning, creativity, and innovation in both face-to- face and virtual environments. Teachers: a. Promote, support, and model creative and innovative thinking and inventiveness 2 - Created by David Brannan – January, 2012 Technology Integration Hardware and Software Needs ● Computer lab or laptop cart with one Internet connected device per student. ● Classroom LCD projector ● External Speakers (optional) Tips and Tricks Work with your Instructional Technology Teacher to set up accounts on Prezi.com so students can work in groups or as individuals. Resources Handouts or Downloads Display on LCD projector, printout, or have students reference an online diagram for gaining an understanding of eons, eras, epochs, and periods of Earth’s geologic time. ● Geologic Time Scales http://geology.about.com/od/geotime_dating/a/Geologic-Time-Scale-All-Periods.htm ● Smithsonian - http://paleobiology.si.edu/geotime/main/index.html Web Resources ● Prezi - http://www.prezi.com ● Toilet paper timeline - http://www.worsleyschool.net/science/files/toiletpaper/history.html ● Horizontal Web Timeline - http://www.worsleyschool.net/science/files/time/line.html http://www.worsleyschool.net/science/files/time/line2.html 3 - Created by David Brannan – January, 2012 Lesson Plan Prep Time ● 1 hour to create a Prezi accounts, review Prezi tutorials, and review materials. Prior to Lesson Teacher Prep: ● Schedule the computer lab or laptop cart. Prezi.com is not compatible with Apple’s iOS devices such as tablets due to Apple’s unwillingness to support Adobe Flash. ● Consider collaborating with your Instructional Technology Teacher to help figure learn how to use Prezi. Student Prep: ● None required. Time Needed for Lesson Three 50-55 minute periods recommended. More time may be needed for suggested extensions. Background Knowledge Students should have a basic understanding that geologic time encompasses all the time that has passed since the formation of the Earth, nearly 4.6 billion year ago. Directions – Part 1 Introduction to Geologic Time 1. Initiate a class discussion that addresses what a timeline consists of (scale, key, magnification of sections, etc.). 2. Introduce vocabulary for lesson: eons, eras, epochs, and periods. 3. Provide each group of students with a full roll of toilet paper. 4. Have students unroll their full roll of toilet paper down the hallway. A typical roll contains about 400 squares, and each square is slightly over 11 cm long. 5. The earth is about 5 billion years old. That makes each toilet paper square equivalent to 12.5 million years; each billion years of earth's history takes up 80 squares of toilet paper. 6. On this scale, one year is represented by 0.00000088 cm ... a width too tiny to see. 7. Once the paper is completely unrolled, you can mark these important events in earth's history at the appropriate points: 4 - Created by David Brannan – January, 2012 ● 5 billion years ago: earth is formed, along with the other planets ● 3.7 billion years ago: earth's crust solidified (square 104) ● 3.5 billion years ago: first life appears in oceans (square 120) ● 3.25 billion years ago: photosynthesis begins in oceans (square 140) ● 2.4 billion years ago: oceans contain significant amounts of oxygen (square 208) ● 1.9 billion years ago: first cells with nuclei appear in oceans (square 248) ● 0.65 billion years ago: first multicellular organisms appear (square 348) ● 0.5 billion years ago: first land plants with inner vessels (square 359) ● 250 million years ago: mass extinction of 99% of all life (square 380) ● 245 million years ago: Age of Dinosaurs begins (square 380) ● 150 million years ago: Supercontinent breaking up; continents drifting apart (square 388) ● 65 million years ago: Age of Dinosaurs ends, with mass extinction of 70% of all living things (square 394) ● 3.5 million years ago: First proto-humans appear, in what is now ● Africa (last square, 3.1 cm from end) ● 100,000 years ago: First Homo sapiens appears (last square, 1 mm from end) ● 10,000 years ago: Recorded human history begins (last square, 0.1 mm from end). Note: The idea of the toilet paper timeline is to make a very dramatic statement of the age of the Earth, especially when discussing geologic time. Directions – Part 2 Students will work towards building their own timeline using Prezi.com where they can include eons, eras, epochs, and periods of time. Students can go into great detail adding Earth’s major events through pictures, videos, text, and animation. Students can work collaboratively. 1. Take students to the school’s computer lab and/or hand out laptops from the cart within your own classroom. 2. Demonstrate through an LCD projector how to create an account at Prezi.com. 3. Run through Prezi’s opening tutorials on how to create a Prezi (5 minutes). 4. Model for students how to access the basic template for timelines. 5. Instruct students to create a timeline that dates back at least 4.6 billion years and is divided into 100 million year increments. 6. Instruct students to access About.com (see web resources) to find the eons, eras, epochs, and periods of time in Earth’s history. 7. Guide the students as they accurately put these periods of time into their Prezi timeline. Hint: Have the students color code each one. 8. After students have labeled the eons, eras, epochs, and periods on their timeline, then have students access Smithsonian website (see resources) and label at least three periods of mass extinction. 9. Have students share their timeline with the class or in small groups. 5 - Created by David Brannan – January, 2012 Extension / Challenge Math can be incorporated by: ● Students working on scale factors in math class in order to be more successful with the creation of their timeline. ● Emphasizing a magnification of a particular piece of the timeline to show greater detail of the most recent period of time. Students can then include major scientific discoveries for the past 100 years. Global Studies can be incorporated by: ● Students working on major historical events magnified in detail on a timeline. ● Working on essay questions pertaining to the rate of evolutionary changes in societies compared to the rates of biological changes in species. 6 - Created by David Brannan – January, 2012 .
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