Head to Fish Creek or Nose Hill or Glenmore Reservoir for some biking, jogging, fresh air. Chase a deer!
Hit up downtown on the weekend and try to find a new watering hole, try a new restaurant, and search out some local music. Stop at a patio of the weather is nice.
Golf season is starting and there are lots of courses in and out of the city.
The underground movie festival will be on us soon. Same with spoken word festival. And the Comic Expo.
Shoot, here's a list of Spring festivals in Calgary.
http://en.wikipedia.org/wiki/List_of...als_in_Calgary
As MMF said, the mountains are there, beckoning.
Join the sport and social club, play some sports, meet some girls, drink some beer.
Brand new science center has been built, maybe it's more for kids, but probably fun to check out once.
Zoo, Heritage Park, not my things but many like them.
LOTS of things to do in Calgary.