Scientists have estimated that the Earth is about 4.6 billion (4,600,000,000) years old! Geologists and paleontologists have made a timeline of the Earth's history called the geologic timeline. This timeline is divided into chunks of time based on fossils we find from each one. These large chunks of time are called eras. Sometimes eras are further divided into periods. The Mesozoic era, when dinosaurs ruled, is divided into the Triassic, Jurassic, and Cretaceous periods. You can look at how the different eras are divided in the geologic timeline shown.
Each era is represented by a unique group of organisms that lived together during that time. Each era and period has been given a designated range of years. For example, the Triassic period lasted from 252 million years ago to 200 million years ago. Sometimes an organism only lived for part of an era or period. If a species only lived from 215 million to 200 million years ago, we would say that it lived in the Early Triassic.
The kids will get a print our of a similar geologic time sheet with the blanks where the different time zones are and they will go around the room and fine the different answers and then come back and place them in the right timeline that we learned about.'
The time zones should be written in large letters on colored paper, as to be able to see them easily.