Toronto Island is one of those places that I wish I spent more time at. Unfortunately, my laziness and need to be employed stop be from lollygagging my days away in this true Toronto treat. There is tons of park space, with plenty of room to do all your favorite park things including throw a Frisbee/baseball/football/tennis ball, kick a soccer ball and have a delicious barbecue or picnic.
There's lots of other things to do, too, including a water park, or go to a concert. I've even heard that there's a Frisbee golf course somewhere around here, although that may just be wishful thinking (but I don't think so!) There's also a haunted lighthouse (yep) that you're not allowed to climb up anymore, but it's still a fun bit of trivia.