Earth Day is the largest secular observance in the world. Celebrated by more than a billion people every year, Earth Day encourages people and governments around the world to take action to protect our shared environment. Take our quiz to test your knowledge of this long-running day of action:
Quiz: Test Your Earth Day Knowledge
Earth Day 2018 is Sunday, April 22. Take our quiz to test your knowledge of this long-running holiday dedicated to protecting our shared environment.
