On the long weekend, my wife and I took a trip out past Nordegg to Siffleur Falls. If you are looking for a great day trip I would totally recommend this area. The actual  hike to the falls includes walking over a couple bridges (one of them a suspension bridge), a boardwalk over a protected area, and then an uphill hike up to the falls. I wouldn't recommend it if you have smaller kids, or if you are not in the best of shape. It takes about 40 minutes to get up to the waterfalls area. 

Siffleur Falls are located west of Nordegg  on highway 11. It is about a 2.5 hour drive with lots of nice scenery along the way.