I suggest you load up the car, get on the 401 and drive over the 2nd narrows, take the Mt. Seymour Parkway exit and drive up the mountain. Hike up to Mystery Lake and beyond. At the end of the day come back to the lake and cool off. It is the best day a family could have - been doing it since the 60s. And don't bother paying for parking. They don't enforce. Apparently only half of the parkers pay, since they implemented pay parking three or four years ago.