Donations - either from corporations or individuals - are always appreciated. 

After the course, you are trusted to donate whatever you believe is fair for the value you received.  If you were informed about the course by a charity or non-profit group, your donation should go directly to that charity or group which can then issue an official receipt . In Canada, the easiest way to do that is to use the website CanadaHelps.org.  It lists all the approved charities in Canada so you can find the one you wish to donate to.  Then your tax receipt will be issued by CanadaHelps.org.

If no charity or group invited you to the course, the donation should go to Plan, a world-wide charity operating in over 50 countries. Choose Plan Canada if you are Canadian, and Plan USA if you are American so you will receive the appropriate tax receipt.  Use the donation links on the Home Page.