Curated OER
Earth Science Lesson Plans The Proterozoic Era
Learners explore the Proterozoic Era. In 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.