Good news! The public transit system in Montreal (STM) has recently changed its policy regarding who can get a student rate on their OPUS card: Kids under 16 years no longer have to show proof of school attendance or have a permanent code! They just need an ID with proof of age, and a parent's signature if they are under 14.
I read it here and went down to SPEQ Photo to confirm it. And it's true! Spread the word...