In this 6-part activity, students learn about climate change during the Cenozoic and the abrupt changes at the Cretaceous/Paleogene boundary (65.5 million years ago), the Eocene/Oligocene boundary (33.9 million years ago), and the Paleocene/Eocene boundary (55.8 million years ago).

Climate has varied in the past, but today's climate change rate is much more drastic due to human activity. Students explore past climate cycle graphs and compare the cycles with the current rate of change.