What are some events that all of us have had in our lives? Ask the class "What are some events that all of us have had in our lives?" Make a list of 5 or 6 things on the board. Let’s organize these!

Humans have walked the Earth for 190,000 years, a mere blip in Earth's 4.5-billion-year history. A lot has happened in that time. Earth formed and oxygen levels rose in the foundational years of the ...