Which province are you planning on settling in, jabed?
I assume you wouldn't be going the usual high school approach, but would be using a charter school or similar?
Education in this province is frighteningly rounded. Sport is practically a religion. Yep, the kids do band. The regular 'lessons' themselves are essentially death by worksheet, with little or no differentiation for individuals (despite a provincial claim that this happens). Teachers leave the building approximately 60 seconds after the bell signals the end of the day, and arrive ten minutes before (there is definitely not the same cultural expectation as in the uk that teachers work 9-5 or longer, lesson planning etc, there is really no need, everything is taught from a work book every year). Teaching is a very different kettle of fish, as is learning. We are considering he for ds1 (going into grade 6) as he is definitely not thriving in such a boring unchallenging and rigid environment. He needs a whack of out of the box extension to keep him interested. (this is despite psych reports saying that he needs extension work, and a gifted dx recognized by the school).
I know teachers from the uk who have really struggled with the ethos of education in Canada. The idea of leaving early and getting days off in lieu of parent's meeting is a lovely one, but the 'teaching' is a completely different ball game.
That said, the girls seem to be thriving. Dd1 was one of two kids from the school selected for a mentorship programme (in reality she isn't as gifted as ds1, but is a hard worker), but these opportunities have been cut back due to funding.
A lot of parents do see Canada as a superior alternative to the UK in terms of children's upbringing, though - Jabed is bog standard issue from a potential immigrant's pov on that one. Teens are on the whole more socially adept, capable of having conversations with adults (even strangers) and there is less of the whole swearing and rudeness in public. The same issues exist with drug culture etc, of course, it's just that the kids can smile and talk to you before they party hard. 
Def not going to continue the same boring convo about the militaristic side of the scouts, but most of the girls here are defecting to scouts because it's a jamboree year and they all want to go...
On the summer camp side, the uni in the city (an hour or so away) runs science and math summer camps which are suitable for gifted kids. That said, you can never get on them because they are stuffed to the brim with kids with pushy parents.
Ohhhhhhh, it's just struck me. Jabed, are you planning on getting ds into a gifted school over here? If so, you'd better plan on moving to the city... Most have pretty tight catchment areas...