Hi ~ I have a 3 and 9 year old so I can help you out with a lot of fun kid things to do!
CANADA'S WONDERLAND IS GREAT! The water park alone is worth a full day of fun! We have been season pass holders for two years in a row. I have been thinking about buying them again this year. Season's passes are about the same price as two days, so if you think you'll go 2 or more days, you might consider the pass. We take picnic lunches (they are allowed now) and it saves a lot of time and money! We even took our passes to Paramount King's Island in Ohio and got into the park FREE with the passes.
Toronto Island is a nice way to see the cityline ~ pretty flowers, great pier, bike rentals. The petting zoo is fun too. I find the ride great for preschoolers. They have a few big kid rides. I think the ferry is only 7 or 8 minutes ~ I timed it even with my finger nails embedded into the sit. (Sandra don't like boats).
Are you Outdoorsy? Halton Conservation Authority has fabulous parks and trails. We love swimming at Kelso, hiking Rattlesnake Point and trail walking to Hilton Falls. Mountsberg is awesome for bird watching.
Fantasy Fair indoor amusement park in Woodbine Centre is so much fun! They have 9 full sized amusement park rides perfect for your kids ages. It's right across the street from Woodbine Race Track. My kids love having a hot dog and watching the horses race. We even let dd (9) pick a horse for a $2.00 bet. They also have a great slot machine area but that's just for adults.
Chuck E. Cheese in Mississauga is a favourite haunt for us!
Rainforest Cafe in Yorkdale is great and we always visit the
Disney Store after we eat!
There is so much to do here! Let us know when you come up and maybe we can do a DISmeet! Sandra