Title: Geologic Time Scale I

Author:
Tamara McDaniel, Lake Geneva Middle School 600 Bloomfield Rd. Lake Geneva, WI 53147
Tamara.mcdaniel@badger.k12.wi.us

Grades: 7-8 (Spiraled) (See Geologic Time Scale II for the 8th grade activity)

Overview of Lesson:
Students will research the geologic time scale. They will...
  1. Identify the four eras.
  2. Indicate the time span of each era.
  3. Classify major events of each era.
  4. Create and recognize the importance of making a geologic time line.
Suggested Time: 3 periods of 45 minutes

Students' Prior Knowledge: This activity is geared for students that have very little or no knowledge of the geologic time scale. To see how much the students know, give them the Geologic Time Scale Questionnaire sheet. This is a good pre-test to see what they know about the geologic time scale. If they know most of the information, you may want to proceed to the 2nd activity (8th grade activity) of this spiraling lesson. The 8th grade activity is designed to build off of the 7th grade activity. Once the students have completed the Questionnaire sheet, collect them and look through the answers. Their answers will determine whether this activity is suited for their ability. If this activity is suited for their ability, hand back the Questionnaire sheet and continue with the Student Activity “Making a Geologic Time Line”. Do not go over the answers to the Questionnaire until the Student Activity is complete.
Students should be familiar with the words: geology, fossil, and time line.

Background Information: As a prelude to this activity, have the students fill out the Geologic Time Scale Questionnaire. This will be their pre-test and study guide for the activity. They will complete a Student Activity “Making a Geologic Time Line”, in which they will make a geologic time line. When this is completed, they will be given a Final Assessment “SHOW ME YOUR FINDINGS!” During that time they will justify what they have learned from this activity.
Side note: It is important to encourage the students to keep the Questionnaire sheet with them throughout the activity and use it as a note taking sheet and study guide. Also, encourage them to make corrections and alterations on it when necessary.

The students will be researching the geologic time scale for this activity. It is important to show them many different forms of the geologic time scale and to show them that the dates may differ among various forms of the time scale. The geologic time scale covers billions of years, and scientists are still making adjustments and alterations as they uncover new findings. This makes a geologist’s job very important; in fact it is crucial to unraveling the history of the earth. The students will be creating a geologic time line, which will include labeling each of the 4 eras, the time of each era and major geologic events of each era. They will use the geologic time scale for this activity.

Materials: (per student)
Student Activity:
Making a Geologic Time Line

Final Assessment:
Show Me Your Findings

Teacher Notes:
Answer Key: Geologic Time Scale Questionnaire
  1. Answers will vary
  2. About 4.6 billion years old
  3. 65 million years ago or at the end of the Mesozoic Era
  4. 245 million years ago
  5. No
  6. A system of showing various blocks of time in the Earth’s history in an orderly arrangement.
  7. Mass extinction usually marks the end of an Era. For instance, the dinosaurs became extinct as well as many other animals about 65 million years ago. The greatest extinction occurred about 245 million years ago, which marked the end of the Paleozoic Era.
  8. Cenozoic Era
  9. D = about 65 million years ago (End of Mesozoic)
    R = about 3.5 billion years ago (Precambrian)
    H = about 4 million years ago (Cenozoic)
  10. Answers will vary.
  11. Answers will vary.
Answer Key: Final Assessment “SHOW ME YOUR FINDINGS!”,
  1. Precambrian = 4.6 billion to 545 million
    Paleozoic = 545 million to 245 million
    Mesozoic = 245 million to 65 million
    Cenozoic = 65 million to present
  2. Cenozoic Era
  3. About 4.6 billion years old
  4. Mesozoic Era
  5. Mesozoic Era
  6. Fossil evidence
  7. A system of showing various blocks of time in the Earth’s history in an orderly arrangement.
  8. Mass extinction usually marks the end of an Era. For instance, the dinosaurs became extinct as well as many other animals about 65 million years ago. There was another mass extinction about 245 million years ago, which marks the end of the Paleozoic Era.
  9. D = about 65 million years ago (End of Mesozoic)
    R = about 3.5 billion years ago (Precambrian)
    H = about 4 million years ago (Cenozoic)
    P = about 545 million years ago
    M = about 245 million years ago
    C = about 65 million years ago
  10. Answers will vary.
Vocabulary:
geologic time scale, eras, scale, time line

Extension Activities:
*Language Arts: The student may complete a creative writing assignment: When will the era that we live in end, and what will the next era be named?
*Science: Instead of using a time line to show the eras, the students could use a clock to show the eras. By using the ratio 24 hrs = 4.6 billion years, they could calculate the hours needed for each era.
*Science: Instead of using 5 meters for this activity, a longer distance could be used and the students could walk to the geologic time scale. Use 500 meters instead of 5 meters.

Interdisciplinary Connections:
Math: The students will practice measuring using a scale
Language Arts: The students will be deciphering the term geologic time scale by using encoding skills.

Resources:
Denver Earth Science Project, Colorado School of Mines
Dinosaur Lake by Marin G. Lockley, Barara J. Fillmore, and Lori Marquardt
Colorado’s Dinosaur by John T. Jenkins, Jr. and Janice L. Jenkins
The Illustrated Encyclopedia of Dinosaurs by Dr. David Norman
University of Wisconsin Madison Geology Museum www.geology.wisc.edu/~museum

Wisconsin State Science Standards:
A.8.4.
http://www.dpi.state.wi/standards/scia8.html
Collect evidence* to show* that models* developed as explanations* for events were (and are) based on the evidence available to scientists at the time.

B.8.1.
http://www.dpi.state.wi.us/standards/scib8.html
Describe* how scientific knowledge and concepts have changed over time in the earth and space, life and environmental, and physical sciences.

C.8.1.
http://www.dpi.state.wi.us/standards/scic8.html
Identify* questions they can investigate* using resources and equipment they have available.

C.8.11.
http://www.dpi.state.wi.us/standards/scic8.html
Raise further questions which still need to be answered.

E.8.1.
http://www.dpi.state.wi.us/standards/scie8.html
Using the science themes*, explain* and predict* changes* in major features of land, water, and atmospheric systems.

E.8.5.
http://www.dpi.state.wi.us/standards/scie8.html
Analyze* the geologic and life history of the earth, including change* over time, using various forms of scientific evidence.

F.8.9.
http://www.dpi.state.wi.us/standards/scif8.html
Explain* how some of the changes* on the earth are contributing to changes in the balance of life and affecting the survival or population growth of certain species.