I've put together a collection of creation myths from a variety of civilizations around the world, as well as created a handout for students to complete in groups. There are many creation myths out there, and some civilizations have multiple myths to explain their existence.
These, I've gathered and used over the years, and have modified the wording on some to improve clarity for students:
I generally use this at the beginning of the year in my World History class. I recommend using this after students have learned about the rise of hominids. It's a great reading activity at the beginning of the year for students to practice reading strategies in the Social Studies and working in groups.