I love the Smokies. I try to go 1-2 times per year. Let the kids play in the creeks, because it should be hot enough in August and that is free. Stop at the Sugarland Visitor Center and there is a rather short hike for the Cataract Falls. From there head into the park and either head towards Cade's Cove, or towards NC. If you head towards NC there are many stops and pull offs you can take. I highly recommend the Mingo Waterfall, which is near Cherokee. Not much to do in Cherokee(casino) but it is a waterfall I really like. I also like the Chimney Tops Trail and the Alum Cave Bluffs (I think it's closed for renovations).
My children enjoyed Dollywood, but I would only go for a day, or maybe two at most. I hear many complaints of traffic and have been in September and didn't find it bad that month. I go in October which is usually a peak month, and I guess i'm odd but the traffic doesn't bother me too much. We stayed at a Clarion Inn on the strip in Gatlinburg and I loved the location because it was about as close as you could get to the National Park and we had several nice restaurants in walking distance. I like riding the tram at Ober Gatlinburg and there is an old ice skating rink. That building is a bit out dated. Riding up the sky lift in Gatlinburg is another think i've only done a few times but truly enjoyed. I love to go to the Fannie Farkle arcade place for the grilled sausage!!!!! My kids love to play the arcade there. They have a space needle that a man recently committed suicide from

I did this walking tour at night that was about Ghost Stories- there were a few companies who did that (one was more cheesy, with costumes, but the one I went one told a bit about the history of the city and I enjoyed that). On the Roaring Fork Motor Trail, which is off of this Orchard Tree Rd, there are a couple of waterfalls, and a couple of nice mountain views- it has a few old homesteads which kinda makes it's similar to Cade's Cove. I never seem to see animals besides a squirrel on the Roaring Fork Trail, but people claim to see bears and deers.
The Ripley's Aquarium is very nice, but look at weather forecast for a rainy day/or worst weather day.
I love going to "The Christmas Place" in Pigeon Forge..I guess it's and odd tradition, but I love to get a personalized ornament and look around. The Apple Barn is a popular restaurant- it's just kinda like Cracker Barrel to me. They did have the big hot air balloon thing like Disney, and plenty of places to zipline, The Titanic place, WonderWorks, and plenty of dinner shows including the Dixie Stampede. We like to pull into the parking lot and look at the horses from their stalls at the Dixie Stampede.