Are French schools part of this?
The Montreal Private School Expo includes both English and French speaking schools. You may wish to browse some of the exhibiting schools here: http://www.ourkids.net/expo/exhibiting-schools.php
We also have some information on certificate of eligibility on our site here: http://www.ourkids.net/english-language-schools-montreal.php#cert as well as a list of English language schools, including a number of schools that do not require a certificate to apply.
You may also be interested in browsing some important questions to ask schools here: http://www.ourkids.net/school/questions-to-ask-schools.php