A teach-in is a forum or discussion that focuses on a specific political issue and involves audience participation. The first teach-ins were held during the Vietnam War.
Unlike a more formal lecture, a teach-in isn't only intended to educate, but is organized to invite questions and discussion. Most teach-ins focus on controversial or complex topics, and they usually include brainstorming about practical action participants can take. Besides anti-war teach-ins, they might center on corporate power, environmental issues, or racism. A University of Michigan anthropologist is credited with coining teach-in in 1965, inspired by sit-in.