Estrella Mountain Community College
Online Biology Book: Paleobiology: Fossils and Time
Find out how fossil evidence has been the major link to learning about Earth's geologic history. See several illustrated interpretations of a geologic time scale in this online biology textbook.
Open Curriculum
Open Curriculum: Multicellular Life
To describe the diversity of unicellular organisms which arose over 2 billion years of evolution.
Open Curriculum
Open Curriculum: Studying the History of Life
This in-depth article illustrates the concept of geologic time, and helps the learner understand why fossils are rare.
University of California
University of California Museum of Paleontology: Geologic Time
Learn about geologic time, including the age of the Earth by putting it in terms of pages in a book.
Science Education Resource Center at Carleton College
Serc: How Many Is a Million?
A visualization activity where students can conceptualize the age of the Earth by observing dots on paper, making calculations and estimations, and discussing their findings with classmates.
Georgia Department of Education
Ga Virtual Learning: Geologic Time and Correlation
In this amazing interactive tutorial you will learn about what methods are used by geologists to learn about the history of the Earth. Investigate a geologic time scale and learn about how scientists have developed and organized a record...
Georgia Department of Education
Ga Virtual Learning: Historical Geology
In this interactive tutorial you will explore how geologists use clues in rocks to determine the order in which rocks formed. Learn how principles of radioactivity are used to assign actual ages to rocks. Students will explore fossils...
American Geosciences Institute
American Geosciences Institute: Earth Science Week: Texas Rocks
For this investigation, students start exploring the U.S. Geological Survey's (USGS) online version of the geologic map of Texas. The geologic time scale shown will help them figure out how old the rocks are in various parts of Texas.
Smithsonian Institution
Smithsonian Science Education Center: Time: It's Like, So Deep
This video reviews over geologic time scale and methods to teach this appropriately in the classroom. [9:15]
TeachEngineering
Teach Engineering: Fantastic Fossils
Students learn about fossils - what they are, how they are formed, and why scientists and engineers care about them.
CK-12 Foundation
Ck 12: Earth Science: Life and the Geologic Time Scale
[Free Registration/Login may be required to access all resource tools.] Describes relationship between evolution and the geologic time scale.
CK-12 Foundation
Ck 12: Biology: History of Life
[Free Registration/Login may be required to access all resource tools.] This comprehensive lesson by CK-12 explains how scientists learn about the past by examining and dating fossils.
CK-12 Foundation
Ck 12: Life Science: Timeline of Evolution
[Free Registration/Login may be required to access all resource tools.] For life to evolve from simple single-celled organisms to many millions of species of prokaryotic species to simple eukaryotic species to all the protists, fungi,...
CK-12 Foundation
Ck 12: Biology: History of Life
[Free Registration/Login may be required to access all resource tools.] Describes how scientists learn about the past by examining and dating fossils.
PBS
Nova: A Brief History of Earth
This timeline is a good resource if you are looking for brief descriptions of the geologic periods. Descriptions include pictures of common organisms for each period and the range of time covered by each period.
American Geosciences Institute
American Geosciences Institute: Earth Science Week: Houston Activity: Texas Rocks
Using a geologic time scale and map students investigate the rocks in their area.
CK-12 Foundation
Ck 12: Earth Science: Geologic Time Scale
[Free Registration/Login may be required to access all resource tools.] How the geologic time scale is divided.
Center for Educational Technologies
Earth Floor: Geologic Time
This is a nice explanation of geologic time and Earth's major eras. Although this site is designed for younger students, it is mostly text with few images.
CK-12 Foundation
Ck 12: Fourth Grade Science: Earth Science: Relative Ages of Rocks
[Free Registration/Login may be required to access all resource tools.] Looks at how stratigraphy can be used to determine the relative ages of rocks, how unconformities occur, ways to match rock layers in different areas, and how...
CK-12 Foundation
Ck 12: Biology: Evolution of Multicellular Life Study Guide
This comprehensive study guide covers the main terms and concepts needed for a unit on the evolution of multicellular life.
CK-12 Foundation
Ck 12: Earth Science: Geologic Time Scale Study Guide
Take a quick look at Earth's geologic time scale.
US Geological Survey
Usgs: What Is Geologic Time?
Understand the evidence for ancient earth and the geologic time scale. Learn on this site how the earth can help scientist date discoveries.