Curated OER
Earth Science Lesson Plans The Proterozoic Era
Middle schoolers explore the Proterozoic Era. For this geologic time periods lesson, students examine the clock of eras charts and listen to a lecture regarding the era.
Other
The Paleontology Portal: Fossil Gallery
An image gallery of fossils through time. Students choose a time period to see what life was like by studying the fossils.
Ohio History Central
Ohio History Central: Time Line of Ohio History
A comprehensive timeline of events in the prehistory and history of Ohio. Hyperlinks to the multitude of specific articles about Ohio's history.
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.