http://www.calendar-updates.com/info/holidays/canada/earth.aspx

Celebrated every April 22, Earth Day is one of the largest, most celebrated, environmental events worldwide.

More than 6 million Canadians join 500 million people in over 180 countries in staging events and projects to address local environmental issues.  Nearly every school child in Canada takes part in an Earth Day activity.

First launched as an environmental awareness event in the United States in 1970, Earth Day is celebrated as the birth of the modern environmental movement. On April 22, 1970, Arbor Day activities were modified to emphasize the critical importance of the environment and to make the American public aware of the destruction of the earth's natural preserves. The sponsors of Earth Day hoped to start an environmental movement that would alter industrial practices and human consumption.

Earth Day is a powerful catalyst for change. The first Earth Day, spearheaded by Wisconsin Governor Gaylord Nelson and Harvard University student Denis Hayes, involved teach-ins that addressed decades of environmental pollution.  It was observed by twenty million Americans, most of them students. The event inspired the US Congress to pass clean air and water acts, and establish the Environmental Protection Agency to research and monitor environmental issues and enforce environmental laws.