Fianlly, an area in which I have expertise - I am constantly amazed at all the info dedicated posters have here. My boys were at the Science Centre for day camp, so we have info about this exhibit.
The Marvel Heroes exhibit will cost you extra - must pay for Science Centre Admission, and then purchase admission to the exhibit (presumably for a specific time period, as for the last blockbuster exhibit, BodyWorlds). We are Gold Members, and we did receive a coupon for 1 free Marvel admission, and I suspect that ALL members received this coupon, not just Gold members. The coupon came with the most recent newsletter, so you should check that you'll get a coupon if you are thinking of joining just for this reason. I'm having trouble with the Science Centre website and haven't been able to check how much the tickets are...maybe $8?
If you live in Toronto and plan to visit the Science Centre a few times in the year, the membership really pays off. We live 10 minutes drive away and we go all the time - that's why we got the gold membership, which includes free parking and unlimited parking. One of our sons is physically disabled, and the Science Centre is a great place for him to walk indoors with his waler in bad weather.
My 7 year old twins are looking forward to learning more about their favourite superheroes' powers!
Twinmum
P.S. The Science Centre summer camps are terrific!