Turn off your lights for "Earth Hour" on Saturday, March 23, 2013, between 8:30 p.m. and 9:30 p.m. 

Over the years, Canada has become one of the countries with the highest rate of participation in this event. Earth Hour is a kind of New Year for the environment which provides us with an occasion to examine where we are at and to determine the measures which we can take or repeat to improve its health.  
 
You can find tools and ideas for activities on the World Wide Fund website and you can also consult their Facebook page.