Hi, I play High school football in Canada!
Cool!  I don't know anything about Canadian football. Is it different from American football?
A bit! In the CFL, the field is longer and the end zones are a bit deeper, but other then that not much!
Has Canadian football been around for as long as US football?
Football was invented by the Canadian James Naismith, so technically it has been around longer!
Interesting! Is football very popular in Canada the way it is in the United States?
I'd like to think it is! We have a lot of enthusiastic young players and lots of High school teams. 
It would be neat if CFL teams ever played against NFL teams. I'm not aware of that happening. But for instance, there are Canadian teams in Major League Baseball.