Cool World Institute's virtual, on-line teach-in on Earth Day, April 22, 2020. That date is the 50th anniversary of the original 1970 Earth Day, in which around 20 million people participated. The original Earth Day included a teach-in, and teach-ins have been an important part of Earth Day ever since. The teach-in will be held in English, will run from 9 AM to 2 PM Pacific Daylight Time, 12 noon to 5 PM Eastern Daylight Time on Wednesday, April 22. It is open to everyone, online, but advance registration is required. The purpose of the teach-in is to enable participants, who are expected to be environmental activists, not lawyers, to use the law to fight for the environment, with an emphasis on fighting climate change. The focus will be on United States law, with some information on U.S. state law and EU law.