If you think the citizenship test is a mere formality, think again! Dominion Institute's research paper shows that 45% of Canadians would actually FAIL the test if they had to write it now. All the questions are based on "A Look At Canada", which is automatically sent to all applicants for Canadian Citizenship, free of charge. You can also download it here.

There are several publications and websites that prepare you for the test. In our opinion, the best deal is offered by CitiTest.com.

cititest
CitiTest offers:
Practice Questions in PDF format (2 levels of difficulty)
Practice Questions by Category (History, Geography, etc)
Free evaluation test (so you know which level to buy)
Free training online (limited to one category, but you can upgrade to have access to all of them)
Real Test Simulations
Random Tests
Audio Support (you can listen to all questions and answers)
Manuals available in Chinese, Punjabi, Spanish, Russian and other languages.
Tips, warnings, "test secrets", recommendations
And much more.

This is by far
the most comprehensive training website dedicated to Canadian Citizenship Test.

Your other option is:

Public Libraries. Most of them have free material available. But not all of them keep their material up to date. Some of them still say that Jean Chretien is our Prime Minister, and the Right Honourable Adrienne Clarkson is still our Governor General. (this is all wrong, of course!)

TestCanada - Practice Questions